Great job everyone, the correct answer is A, C, B!
A has the most specific and detailed tags.
C is close, but the tag "people" is unnecessary, as it's just a single person in the icon. The tags "office" and "business" do not totally belong either, as they're a bit vague for what's shown. A better alternative would have been "business man".
B has too many tags (more than 7, which lowers its ranking in the search results), and most of its tags are are way too general and do not reflect what's shown in the icon. For example, a student should be present in the icon if the tag "student" is to be used.