prep 35 请高手指点下

whitebone008

In laboratory rats, a low dose of aspirin usually suffices to block production of thromboxane,
which is a substance that promotes blood clotting, but not seriously interfering with the
production of prostacyclin, which prevents clotting.
(A) which is a substance that promotes blood clotting, but not seriously interfering
(B) a substance that promotes blood clotting, but not seriously interfering
(C) a substance that promotes blood clotting, but does not seriously interfere
(D) which is a substance to promote blood clotting, but does not seriously interfere
(E) which is a substance that promotes blood clotting, but not a serious interference  


D 选项 有何问题？？？

以后再说

选B？

which be, that be, who be 出现，基本就是啰嗦

cooldavy

我看选C吧，同位语比which从句简洁