Well Ankit0411, please understand and learn to reason the options or the answer choices.
The OA for this question is clearly an A and not D. I have seen this question in the GMATprep as well and the correct answer is A.
And the correct reasoning for the answer is as follows:-
Option A:- Lets say the theatre in all sells 10 products including the popcorns and other refreshments.
In those, the option A states that ' Total sales of all refreshments at Moviemania’s movie theaters increased by less than 5 percent last year.'
If I say that out of all the 10 products sold by the theatre, popcorn dipped or made in canola oil was having the maximum sales % increase, then the argument gets weakened as we want.
Practical example:- If I say that Reliance has so many businesses and if a particular Reliance Industries has given more growth than any other business line, then genuinely there is growth right.
With Option D:- No. of people attending the mall is not sufficient to answer the question whether they had the popcorn or no. If you go to the mall, do you confirm have the popcorn.
Another thing, GMAT is not about the only the right answer. It is about why the right answer is right and why the wrong answer choices are wrong.
If you learn to reason, then you can ace the GMAT>
Hope this helps.