many times he finally understood itA. ToldB. TellingC. Having toldD. Having been told

问题补充：

many times，he finally understood it．

A. Told

B. Telling

C. Having told

D. Having been told

答案：

A. Told

B. Telling

C. Having told

(答案→)D. Having been told

解析：本题考查非谓语动词。句中He与tell构成被动关系，本题强调已经被多次告知，应该使用完成时。所以选择D。句意：被告诉了多次，他最终理解了。