If we vertically scan options, we have comparison error, so go option by option and check parallelism.

In option A, "those......." refers to "production", which is singular. Eliminate

In Option B, "1978 harvest" is compared to "production".....Correct

In Option C, "1978" is compared to "production" We cannot compare "year" to "production".......Eliminate

In Option D, "1978" is compared to "production" We cannot compare "year" to "production".......Eliminate

In Option E, "that....." refers to production....."production of India's 1978 harvest" does not make sense. ....... Eliminate

Just out of curiosity, Should not phrase 'In 1979 lack..' be 'In 1979, lack...'?

Because first one seems to say, Sentence description is in 1979 whereas, in the next sentece,year1979 seems to have passed.

Please let me know, if my reasoning is incorrect

Posted from my mobile device

avinashiitp You're right that we would normally follow a time modifier of that sort with a comma, but I'm not seeing the effect on meaning that you describe. The meaning seems clear either way. Perhaps that's why the GMAT didn't bother with a comma on this one.
_________________

egmat need your help in this one. WHy option E is not right?

Have you checked out this post?
_________________