It was clear that he was ______ the people he owed money to. [ ]

A. at the expense of

B. at the risk of

C. at the mercy of

D. in the way of

肺含铁血黄素沉着症的临床可表现包括（）

A.低热

B.咯血

C.不明原因的贫血

D.皮肤淤点

E.呕血