Error Spotting – Choose the single segment (A–D) that contains a grammatical or spelling error; select ‘‘All correct’’ only if the entire sentence is correct. Sentence: A) The philosophers B) believe that by making men see C) reason through argument, society would be changed and human behaviour D) improvd

Introduction / Context:
This sentence blends abstract reasoning with predicted social outcomes. The exam tests straightforward spelling and parallelism at the end of a long clause. Spotting the truncated past participle “improvd” is essential to restore grammatical completeness and stylistic symmetry.

Given Data / Assumptions:

• Main frame: “The philosophers believe that … society would be changed and human behaviour …”
• Desired parallel passive complements: “would be changed” and “(would be) improved”.
• Actual ending: “improvd,” a misspelled and incomplete form.

Concept / Approach:
When coordinating two results, keep the grammatical shape parallel. Here, both results are past participles in a passive result pattern: “changed” and “improved.” Correct spelling also matters in formal evaluation contexts.

Step-by-Step Solution:
1) Identify coordination: X “would be changed” and Y “would be improved.”2) Detect the spelling/inflection error: “improvd” → “improved”.3) Corrected close: “... society would be changed and human behaviour improved.” (Ellipsis of the second “would be” is acceptable for concision.)4) Conclude D is the erroneous segment.

Verification / Alternative check:
Read aloud with “improved”; the parallelism with “changed” becomes clear and the rhythm smooth.

Why Other Options Are Wrong:

• A–C: Grammatically acceptable; the long clause properly introduces a predicted outcome.

Common Pitfalls:
Overanalyzing tense choices and missing simple orthographic mistakes; adding unnecessary auxiliary verbs that break the concise parallel structure.

Final Answer:
improvd