Though the teacher had explained it three times, many students still felt ____. It was so difficult a

physics problem.

[      ]

A. amused

B. excited

C. frightened

D. confused

男性，35岁，胃区常隐痛3年，与饮食有关，间有黑便。检查：血红蛋白75g/L，红细胞3.1×10¹²/L，白细胞5.9×10⁹／L，血小板130×10⁹／L，患者贫血的最大可能的诊断是（）

A.慢性肝病贫血

B.缺铁性贫血

C.营养不良性贫血

D.巨幼红细胞性贫血

E.溶血性贫血