Which of the following statements best describes the impact of a valuation allowance on the financial statements A valuation allowance:（）

A. increases reported income, reduces assets, and reduces equity.  

B. reduces reported income, reduces assets, and reduces equity.  

C. increases reported income, increases liabilities, and reduces equity.

对心肌可产生直接抑制作用的麻醉镇痛药是（）。

A.吗啡

B.芬太尼

C.舒芬太尼

D.哌替啶

E.阿芬太尼