It is not always easy for the general public to see use a new invention can be of to thei

问题补充：

It is not always easy for the general public to see use a new invention can be of to their daily life.

A. which

B. what

C. that

D. whose

答案：

A. which

(答案→)B. what

C. that

D. whose

解析：考查名词性从句。谓语see后面是宾语从句，that引导宾语从句时，没有词义；which在名词性从句中意为“哪一个”。句意：对于一般的民众来说，看到一项新发明给他们的日常生活带来什么样的作用，并非总是易事。be of use相当于useful，意为“有用的”。what use什么作用，故选B。