Is that a book on farming? I want to borrow it.A. So it isB. If soC. So is itD. So if

问题补充：

Is that a book on farming?,I want to borrow it.

A. So it is

B. If so

C. So is it

D. So if

答案：

A. So it is

(答案→)B. If so

C. So is it

D. So if

解析：B解析：句意为：那是一本关于农业的书吗?如果是的话，我想借。so it is的确如此，表观点.看法一致；so is it它也是；so if没有这种表达法；if so如果这样。本句是if it is so的省略，故选B。