Tom pretended it, but in fact, he knew it very well.
A. not listen to
B. not to hear about
C. not to have heard about
D. to be not listening to
网友回答
A. not listen to
B. not to hear about
(答案→)C. not to have heard about
D. to be not listening to
解析：考查不定式用法。本题中的动词pretend后面要接不定式的形式pretend to do sth假装做某事；句意：Tom假装没有听说过这件事情，但是实际上他很了解这件事情。根据句意说明他知道这件事情，那么应该使用不定式的完成式，根据句意说明使用否定式。故C正确。