Sentence improvement — Choose the most idiomatic and temporally accurate wording for this civics/history sentence: ‘‘In India today many of our intellectuals still talk in terms of the French Revolution and the Rights of Man, not appreciating that much has happened since then.’’ Keep the time reference ‘‘since then’’ and ensure the aspect is standard, formal, and precise for SEO-focused English usage.

Given data
In India today many of our intellectuals still talk in terms of the French Revolution and the Rights of Man, not appreciating that much has happened since then.

Concept/Approach
The phrase ‘‘since then’’ requires the present perfect to connect a past reference point with relevance to the present. ‘‘has happened’’ correctly expresses completed change up to now.

Step-by-step evaluation
much has been happening — Present perfect progressive suggests ongoing activity, not a completed span of historical change; less apt.much had happened — Past perfect needs another past time anchor; none is provided.much might happen — Hypothetical future; contradicts ‘‘since then’’.No improvement — Retains the correct present perfect with ‘‘since then’’.

Verification/Alternative
Compare: ‘‘Much has changed since then’’ (standard idiom). The given structure mirrors this pattern.

Common pitfalls
Switching to past perfect without a second past reference point; overusing progressive aspect with historical summaries.

Final Answer
No improvement