many times, he finally understood it. A. ToldB. Telling C. Having toldD. Having been told

网友回答

A. Told
B. Telling
C. Having told
(答案→)D. Having been told
解析：考查非谓语动词。根据句意可知先被告诉许多次，故用现在分词的被动Having been told，表示动作先后性。句意：被告诉了许多次，他最终理解了。