He is only too ready to help others seldom refusing them when they turn to him.A. if

问题补充：

He is only too ready to help others, seldom, , refusing them when they turn to him.

A. if never B. if ever C. if not D . if any

答案：

解析：本题考查考生在语境中灵活运用、辨析短语用法的能力，此处seldom，if ever是一个短语，是“从不，决不”的意思。