Answer: D.The greatest recall for the words happened when learning and testing were in the same context (e.g., learn underwater, get tested underwater).
Explanation:
D is the correct option this is because of the fact that if the person will listen the words that belong to the same context and get tested underwater can give indication of the fact that how much the person have listen and interpreted the words although the air was not the medium for the transmission of sound but water was.