885-sectionB-21.关于ing分词修饰问题。

veryglad2cu

A peculiar feature of the embryonicmammalian circulatory system is that in the area of the heart the cells adhereto one another, beating in unison and adopting specialized orientationsexclusive of one another.
(A) beating inunison and adopting
(B) they beat inunison while adopting
(C) beat inunison, and adopt
(D) beating inunison yet adopting（D）
(E) even thoughthey beat in unison and adopt
ABCE不对我都能理解。
可我不知道正确答案D中的beating和adopting的修饰有没有问题。ing分词在句尾，要么修饰句子主语，要么修饰整句话。可是这里它应该修饰的东西是cells~~~cells不是主语啊。。。。


如何解释呢？求助~~~

polkme

cell是宾语从句的主语