Did you have a good time at Laura’s birthday party?Yes indeed. It’s several years

问题补充：

--- Did you have a good time at Laura’s birthday party?

--- Yes, indeed. It’s several years I enjoyed myself so much.

A. when

B. before

C. since

D. that

答案：

A. when

B. before

(答案→)C. since

D. that

解析：when 既然，当……时；before在……之前；since由于，自从……以来；that因此，以至于。句意：你在劳拉的生日聚会上玩得高兴吗？——是的，没错。已经有好几年我没有玩得这么高兴了。结合语境可知下文描述的是从过去某时起到现在的状态，故选C。