请教大全-211中along with的用法

1.        Chronic low-level leaking and the routine discharge of drilling mud and mineral salts present considerable environmental risk during offshore oil drilling.

(A) Chronic low-level leaking and the routine discharge of drilling mud and mineral salts present considerable environmental risk during offshore oil drilling.

(B) The reason offshore oil drilling presents a considerably environmental risk is because of chronic low-level leaking and the routine discharge of drilling mud and mineral salts.

(C) A considerable risk to the environment is presented during offshore oil drilling, where low-level leaks are chronic and the routine discharge of mud and mineral salts.

(D) Offshore oil drilling presents a considerable risk to the environment due to the fact of chronic low-level leaks, and mud and mineral salts are routinely discharged.（A）

(E) Chronic low-level leaking, along with=in addition to the routine discharge of drilling mud and mineral salts, are what make offshore oil drilling environmentally risky.

请问E为什么不对呢？along with 后面要用are还是is呢？

其实你从along with 前有逗号，就可以大略知，它不能做“真实主语”

更进一步说，即使没有逗号，也应该用单数

将along with理解为插入语，你就应该明白了

谢谢！

如果along with前面没有逗号的话呢？后面用is 还是are啊？

有没有 A along with B are/is 这种用法啊？