I was going to take a photo of the world-famous painting when I noticed a saying “No Photo

问题补充：

I was going to take a photo of the world-famous painting when I noticed a saying “No Photographing”.

A. signal

B. sign

C. sigh

D. spelling

答案：

A. signal

(答案→)B. sign

C. sigh

D. spelling

解析：名词辨析。sign标志;标牌手势;暗号; 征兆; signal信号；sigh叹气,叹息spelling拼写；句意：我正要拍那幅名画，在这时我注意到一个牌子，上面写着：不准拍照。