was<\/em> the methodological flaw fully acknowledged.<\/strong> ✅ (b)<\/h2>\nWhy (structure):<\/strong>
\u201cNot until \u2026\u201d at the beginning triggers inversion in the main clause<\/strong>.
Pattern: Not until + time clause + auxiliary + subject + past participle\/adjective<\/strong>
So we need was + subject<\/strong>.<\/p>\nWhy (meaning):<\/strong>
This structure emphasizes delayed recognition<\/strong>\u2014a common academic rhetorical move.<\/p>\nWhy others are wrong:<\/strong><\/p>\n\n- \n
(a) the researchers had<\/em> \u2192 not a valid inversion pattern here; also \u201chad\u201d would suggest past perfect without reason.<\/p>\n<\/li>\n- \n
(c) did<\/em> \u2192 \u201cdid\u201d would require a base verb (did the researchers acknowledge<\/em>), but we have passive \u201cacknowledged\u201d as a participle phrase.<\/p>\n<\/li>\n<\/ul>\nAcademic note:<\/strong>
This is extremely common in high-level academic writing to highlight when<\/em> awareness emerged.<\/p>\n
\n2) The theory, developed<\/em> over several decades\u2026, now faces renewed scrutiny.<\/strong> ✅ (c)<\/h2>\nWhy (structure):<\/strong>
This is a reduced passive relative clause<\/strong>.
Full form: The theory, which was developed over several decades\u2026<\/em>
Reduced form: The theory, developed over several decades\u2026<\/em><\/p>\nWhy (meaning):<\/strong>
\u201cDeveloped\u201d describes the theory as the product<\/strong> of a process.<\/p>\nWhy others are wrong:<\/strong><\/p>\n\n- \n
(a) developing<\/em> \u2192 active meaning (\u201cthe theory is developing\u201d), wrong.<\/p>\n<\/li>\n- \n
(b) was developed<\/em> \u2192 grammatically possible, but less compressed (not wrong English, but not the intended reduced structure).<\/p>\n<\/li>\n<\/ul>\nAcademic note:<\/strong>
Clause reduction signals advanced writing control<\/strong>.<\/p>\n
\n3) Had the underlying premises been sound, the subsequent model would have demonstrated<\/em>\u2026<\/strong> ✅ (b)<\/h2>\nWhy (structure):<\/strong>
Inverted third conditional<\/strong>.
Pattern: Had + subject + past participle<\/strong>, \u2026 would have + past participle<\/strong>.<\/p>\nWhy (meaning):<\/strong>
Unreal past condition \u2192 unreal past result.<\/p>\nWhy others are wrong:<\/strong><\/p>\n\n- \n
(a) would demonstrate<\/em> \u2192 present\/future hypothetical (2nd conditional result), wrong timeline.<\/p>\n<\/li>\n- \n
(c) demonstrated<\/em> \u2192 loses hypothetical meaning.<\/p>\n<\/li>\n<\/ul>\nAcademic note:<\/strong>
C2 texts love counterfactual evaluation (\u201cIf X had been true, Y would have happened\u201d).<\/p>\n
\n4) The data are by no means sufficiently compelling<\/em> to warrant\u2026<\/strong> ✅ (a)<\/h2>\nWhy (structure):<\/strong>
Degree adverb + adjective: sufficiently + adjective<\/strong>
Also \u201cby no means\u201d boosts negativity\/emphasis.<\/p>\nWhy (meaning):<\/strong>
The writer strongly rejects the adequacy of the evidence.<\/p>\nWhy others are wrong:<\/strong><\/p>\n\n- \n
(b) sufficient compelling<\/em> \u2192 missing adverb (\u201csufficiently\u201d).<\/p>\n<\/li>\n- \n
(c) compelling sufficiently<\/em> \u2192 unnatural order; standard is sufficiently compelling<\/strong>.<\/p>\n<\/li>\n<\/ul>\nAcademic note:<\/strong>
\u201cBy no means\u201d + evaluative scale is classic academic critique.<\/p>\n
\n5) The samples were later found to have been contaminated<\/em>\u2026<\/strong> ✅ (c)<\/h2>\nWhy (structure):<\/strong>
\u201cFound\u201d + perfect passive infinitive<\/strong> = earlier event + passive voice.
Pattern: were found + to have been + V3<\/strong><\/p>\nWhy (meaning):<\/strong>
Contamination happened before<\/strong> they found it. And samples received<\/strong> contamination (passive).<\/p>\nWhy others are wrong:<\/strong><\/p>\n\n- \n
(a) contaminating<\/em> \u2192 participle doesn\u2019t fit \u201cwere found \u2026\u201d structure.<\/p>\n<\/li>\n- \n
(b) to contaminate<\/em> \u2192 would mean samples contaminate something else (active), wrong.<\/p>\n<\/li>\n<\/ul>\nAcademic note:<\/strong>
Perfect passive infinitives are a C2 marker for time-layered reporting.<\/p>\n
\n6) Little attention was paid<\/em> to\u2026<\/strong> ✅ (b)<\/h2>\nWhy (structure):<\/strong>
Fixed academic passive collocation: attention was paid to<\/strong>.
\u201cLittle\u201d fronting emphasizes neglect.<\/p>\nWhy others are wrong:<\/strong><\/p>\n\n- \n
(a) paid<\/em> \u2192 missing auxiliary; incomplete passive.<\/p>\n<\/li>\n- \n
(c) has paid<\/em> \u2192 wrong subject (who \u201chas paid\u201d?), wrong construction.<\/p>\n<\/li>\n<\/ul>\nAcademic note:<\/strong>
This is common in academic criticism to avoid naming an agent.<\/p>\n
\n7) The explanation offered is, at best<\/em>, only partially satisfactory.<\/strong> ✅ (b)<\/h2>\nWhy (structure\/meaning):<\/strong>
\u201cAt best\u201d = even in the most favourable interpretation<\/strong>, it is still only partly good.
It\u2019s a limiter + critique.<\/p>\nWhy others are wrong:<\/strong><\/p>\n\n- \n
(a) in best case<\/em> \u2192 not idiomatic in English.<\/p>\n<\/li>\n- \n
(c) in best<\/em> \u2192 incomplete.<\/p>\n<\/li>\n<\/ul>\nAcademic note:<\/strong>
\u201cAt best\u201d is one of the most frequent \u201cpolite but lethal\u201d academic evaluators.<\/p>\n
\n8) What ultimately undermines the argument is<\/em> its reliance\u2026<\/strong> ✅ (c)<\/h2>\nWhy (structure):<\/strong>
\u201cWhat\u2026\u201d clause is a nominal clause<\/strong> acting as a singular subject<\/strong> \u2192 singular verb is<\/strong>.<\/p>\nWhy others are wrong:<\/strong><\/p>\n\n- \n
(a) are<\/em> \/ (b) were<\/em> \u2192 wrong agreement and\/or tense.<\/p>\n<\/li>\n<\/ul>\nAcademic note:<\/strong>
Nominal clauses let you treat an action as an object\/concept\u2014very C2.<\/p>\n
\n9) Rarely do we encounter<\/em> such a comprehensive synthesis\u2026<\/strong> ✅ (b)<\/h2>\nWhy (structure):<\/strong>
Negative-frequency adverb at the beginning \u2192 auxiliary inversion<\/strong>.
Pattern: Rarely + do\/does\/did + subject + base verb<\/strong><\/p>\nWhy others are wrong:<\/strong><\/p>\n\n- \n
(a) normal order \u2192 not acceptable after \u201cRarely\u201d fronting.<\/p>\n<\/li>\n
- \n
(c) \u201chave encountered\u201d could work in other contexts, but the test targets the standard inversion pattern (and \u201crarely\u201d typically pairs with simple present for general truth).<\/p>\n<\/li>\n<\/ul>\n
Academic note:<\/strong>
Used to make claims sound measured and formal.<\/p>\n
\n10) The proposal was dismissed, having failed<\/em> to address\u2026<\/strong> ✅ (c)<\/h2>\nWhy (structure):<\/strong>
Perfect participle clause = earlier cause.
Meaning: It failed first \u2192 therefore it was dismissed.<\/p>\nWhy others are wrong:<\/strong><\/p>\n\n- \n
(a) failing<\/em> \u2192 can work sometimes, but is less clear about sequence; it may sound simultaneous.<\/p>\n<\/li>\n- \n
(b) failed<\/em> \u2192 breaks the participle structure; you\u2019d need a full clause.<\/p>\n<\/li>\n<\/ul>\nAcademic note:<\/strong>
\u201cHaving + V3\u201d is a C2 compression tool for cause-before-effect.<\/p>\n
\n11) The study claims neutrality; nevertheless<\/em>, \u2026<\/strong> ✅ (c)<\/h2>\nWhy (meaning):<\/strong>
\u201cNevertheless\u201d signals contradiction<\/strong>: claim vs reality.<\/p>\nWhy others are wrong:<\/strong><\/p>\n\n- \n
(a) therefore<\/em> \u2192 wrong logic (would imply neutrality causes bias).<\/p>\n<\/li>\n- \n
(b) moreover<\/em> \u2192 adds information, not contradiction.<\/p>\n<\/li>\n<\/ul>\nAcademic note:<\/strong>
This is how high-level writing performs critique politely.<\/p>\n
\n12) \u2026only to the extent that<\/em> its implementation remains provisional.<\/strong> ✅ (b)<\/h2>\nWhy (structure):<\/strong>
Fixed analytic scope pattern: to the extent that + clause<\/strong><\/p>\nWhy others are wrong:<\/strong><\/p>\n\n- \n
(a) which<\/em> \u2192 relative pronoun, not a conjunction for scope.<\/p>\n<\/li>\n- \n
(c) what<\/em> \u2192 cannot introduce this type of clause.<\/p>\n<\/li>\n<\/ul>\nAcademic note:<\/strong>
This is \u201cclaim limitation grammar\u201d: you allow validity conditionally<\/strong>.<\/p>\n
\n13) \u2026assumptions whose<\/em> implications extend\u2026<\/strong> ✅ (b)<\/h2>\nWhy (structure):<\/strong>
\u201cWhose\u201d expresses possession<\/strong> even for abstract nouns.
assumptions\u2019 implications \u2192 whose implications<\/strong><\/p>\nWhy others are wrong:<\/strong><\/p>\n