Step 1: Approach
We find the director of each film and see which names equal Mrinal Sen. Then we compare the set with the options.
Step 2: Films that belong to Sen
Bhuvan Shome from 1969 is his. Calcutta 71 from 1972 is his too, and it belongs to the group of films he made on Calcutta.
Step 3: Films that belong to other directors
Garam Hawa comes from M. S. Sathyu. 27 Down comes from Avtar Kaul. Neither is a Sen film.
Step 4: Choose the matching option
The set is A and D. This is option 2.
Step 5: Why the other options fail
Options 1, 3 and 4 all carry B or C, which are not Sen films. Option 1 has A, B, D. Option 3 has A, B. Option 4 has B, C, D.
Step 6: Recheck by counting
Out of the four films, exactly two come from Sen. That means the answer must name exactly two letters. Options 1 and 4 name three letters, and option 3 names two but includes B, which is not his. Only option 2 names the right two letters, A and D.
Final Answer:
Only A and D are by Mrinal Sen.
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