You can't imagine the difficulty he

网友回答

在这里difficulty后面的这个句子是一个定语从句,the difficulty是先行词,即被修饰词.省略了关系代词that/which,先行词difficulty在定语从句是充当had的宾语.
You can't imagine the difficulty.
He had difficulty jumping into the cold river and .
这样一来就知道为什么填C了.
======以下答案可供参考======
供参考答案1:
我觉得应该是根据并列而不是那个have difficulty (in) doing