The correct answer is C. are flying.
The sentence “Look, many students are flying kites” is in the present continuous tense. This tense is used to describe actions that are happening at the moment of speaking. In this case, the students are flying kites right now.
The other options are incorrect because they are not in the present continuous tense. Option A, are fly, is in the simple present tense. This tense is used to describe actions that happen regularly or habitually. Option B, are
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