Readers are required to the rules of the library and mind their manners.
A. observe
B. confirm
C. review
D. appreciate
网友回答
(答案→)A. observe
B. confirm
C. review
D. appreciate
解析：句意为：读者要遵守图书馆的规定，注意他们的言行举止。observe vt 观察，遵守；confirm vt 确认，确定，证实；review vt 回顾，检查；appreciate vt感激，欣赏。故答案应为A。