The Terracotta Warriors is known ________ one of the most interesting archaeological

discoveries in the world, which is called “the eighth wonder of the world.”

A for                 B to                             C as                             D by

空调机用紫铜管的焊接最好采用（）。

A.电焊

B.银钎焊

C.磷铜钎焊

D.锡钎焊