单项选择题

But for his sickness, he would have joined the Army.

A.要不是他当初病了,他原本会参军的。
B.但是为了他的病,他将已经加入军队了。
C.要不是他当时在生病,他就参军去了。
D.要不是他的病,他已经当兵去了。