－Hello Mary! This is John. You must know why I you.－Oh hello John! Ive waited for thi

问题补充：

－Hello, Mary! This is John. You must know why I you.

－Oh, hello, John! Ive waited for this call since last month.

A. called

B. am calling

C. was calling

D. have called

答案：

A. called

(答案→)B. am calling

C. was calling

D. have called

解析：考查动词时态的用法。两人正在电话通话，而且后面提到的电话也是这个电话，排除了其他时间的电话。所以“我给你打电话”用现在进行时。