Answer: The correct answer is the C) Return in the same manner.
Explanation: Just to elaborate a little on the answers, it can be added that options A, B and D are incorrect. Reciprocate is not to receive money as a gift, a recipe for a cake or a way to congratulate somebody - although you can certainly reciprocate somebody by providing a recipe for a tasty cake, or by giving money or congratulating, if you deem that gesture to be corresponding to what that person did for you. Reciprocate derives from the Latin verb reciprocāre, which can be translated as to make that two things match or correspond each other.