Can’t really help, because there is a dialogue that you have to read in order to answer the questions
The answer would be No because when ever there is “No,” and you are trying to give a negative answer you have to put another no after the “,”
The answer is (a) because compro is bought in Spanish and in the question it says “yesterday he bought the gifts for his mother” so bought would be the best answer. (B) is to buy I guess like I will buy chicken. And (c) is like they bought chicken. How I know this is well I speak Spanish I hope this helps!