I feel the best answer is B) have food allergies.
It is not a problem for students who do not eat lunch so we can rule out C
It does not mention anything about the cost involved so that rules out D
It is a problem if you don't like fish, however, there are a large number of people who have nut allergies and if peanut butter squares are being prepared around any of it that could be an issue.
Do not open that link it takes all your information
I believe it is A, but I wouldn't go by just my answer.
I think subcontinent is the large region separated by water