In my opinion, this is a(n) _____ different matter.

In my opinion, this is a(n) _____ different matter.
A、entirely
B、merely
C、purely
D、fully
【正确答案】：A
【题目解析】：entirely完全地；merely仅仅；purely单纯的；fully充分地，彻底地句意：在我看来，这是一个完全不同的问题。