单选题 I ______ half an hour before she came out of the telephone box and I entered.
   A) waited                           B) have waited
   C) had been waiting                  D) was waiting
【正确答案】 C
【答案解析】“等”这个动作发生在“她才走出电话亭”之前，且一直持续着，所以应用过去完成进行时。句意：我等了半个小时，她走出电话亭，我才得以进去。