The practice of hanging clothes across the street is a common in many parts of the city.A

问题补充：

The practice of hanging clothes across the street is a common in many parts of the city.

A. look

B. sign

C. sight

D. appearance

答案：

A. look

B. sign

(答案→)C. sight

D. appearance

解析： look/appearance外表； sign标志、迹象； sight风景、视力。结合句意，“在城市的很多地方，衣服穿街晾晒已成一道风景。” 故选C项。