请教一个XDF蓝皮书上的问题

请教一个XDF蓝皮书上的问题：

Camus broke with Sartre in a bitter dispute over the nature of Stalinism.

A. in a bitter dispute over

B. over bitterly disputing

C. after there was a bitter dispute over

D. after having bitterly dispute over

E. over a bitter dispute about

答案是A，请问E为什么不行呢？还有over 和 about 的区别是什么呢？请大家指教！感谢！

考dispute over something的用法

E意思上就可以排除呀。