Question

A salty diet may increase the risk of stomach cancer ________ 10 percent, South Korean researchers found in a study of more than 2 million people．

A．at

B．to

C．by

D．for

Answer 1

C

解析這題考查介詞的用法：increase by“增加了”，句意是：鹽份多的食物會增加胃癌的幾率10%。選C。