It's only( )by bus.A half an hours' B half an hour's C half an hour

问题描述:

It's only( )by bus.A half an hours' B half an hour's C half an hour

A half an hours' 本身复数形式就不对.
B half an hour's 通常接ride walk drive等词,表示多少分钟的路程(后面的动词是指用某种交通工具,或者步行)或者是说half an hour's way by bus
C half an hour
所以我认为选C