请教大全的一道语法题目

fiftycents86

        A peculiar feature of the embryonic mammalian circulatory system is that in the area of the heart the cells adhere to one another, beating in unison and adopting specialized orientations exclusive of one another.

(A) beating in unison and adopting

(B) they beat in unison while adopting

(C) beat in unison, and adopt

(D) beating in unison yet adopting

(E) even though they beat in unison and adopt

应该选什么

遥远的绿洲

选D

首先判断出选伴随状语,确定A,D

然后根据逻辑意思选出转折语气,确定D

雨薇

c