一道不明白的LR,谢谢

这个是LSAT 的题,内容很容易却选不对

Educator: Only those students who are genuinely curious about a topic can successfully learn about that topic. They find the satisfaciton of their  curiosity intrinsically  gratifying, and appreciate the inherent rewards of the learning process itself. However, alomost no child enters the classroom with sufficent curiosity to learn successfully all that the teacher must instill. A teacher's job, therefore,_____.

Which one following most logically completes the educatior's argument?

A)requires for the fulfillment of its goals the stimulation as well as the satifaction of curiosity.

B)necessitates the creative use of rewards that are not inherent in the learning process itself.

正项A,为什么不是B?思路应该是什么呢?谢谢!

因为是新题所以没有解释,　多谢了．

自己ding 一下