There are 40 students in our class who come from a of backgrounds.A. varietyB. mixtureC. e

问题补充：

There are 40 students in our class，who come from a of backgrounds.

A. variety

B. mixture

C. extension

D. combination

答案：

(答案→)A. variety

B. mixture

C. extension

D. combination

解析：本题考查名词辨析。variety意为“多样性，种类”，表示“他们来自不同的背景”。mixture“混合物，混合体”；extension“伸长，伸展，延伸，范围”；combination“结合，合并，配合，组合”。