问两道初三竞赛英语题It is generally believed that teaching is ----- it

问两道初三竞赛英语题
It is generally believed that teaching is ----- it is a science.
A an art much as
B much an art as
C as an art much as
D as much an art as
答案是B 但我想知道原因
There are ----- vegetables on the table, but there isn't ----rice in the bowl.
A a few a little
B a few little
答案也是B why?