Answer: Im thinking A probably.
Explanation: NONE
4 es a que hora te gusta estudiar español?
5 es Carolina no le gusta la comida de su escuela
9 es a los niños les gusta comer el chocolate
This could be answered, theoretically, in many different ways. All of which might sound a bit dirty. The translation of the sentence is: "What ___ ___ (to) do to Juan on vacation?" I could fill in the blanks with "tú quieres" which would translate the sentence to "What do you want to do to Juan on vacation?" Without choices, that is the best I got.
8. Le
9. Le
10. Les
I believe thats right