交感和副交感神经节前纤维释放的递质（）
A.肾上腺素
B.去甲肾上腺素
C.乙酰胆碱
D.多巴胺
E.5-羟色胺
参考答案：C
急性左心衰竭时咳出（）
A.腥臭痰
B.白色黏痰
C.粉红色泡沫痰
D.脓痰
E.铁锈色痰
—Is chemistry more difficult than physics?
— No, chemistry isn't as _____ as physics. [ ]
A. easy
B. difficult
C. easier
D. more difficult
