11th OG verbal册102题

Aothough Napoleon's army entered Russia with far more supplies than they had in their previous campaigns, it had provisions for only twenty-four days.

A   they had in their previous campaigns

B   their previous campaigns had had

C   they had for any previous campaign

D   in their previous campaigns

E   for any previous campaign

这道题答案是E，没有疑问

我的问题是E带入原句，其中的comma连接的前后应该是两个完整的句子呀，难道这里不需要一个连接词么？这里是不是run-on了？

又看了11th对于run-on的解释

Run-on sentences: A run-on sentence is two independent clauses that run together without proper punctuation.

Examples:

correct:"Jose Canseco is still a feared batter, most pitchers don't want to face him."

Incorrect:"Jose Canseco is sitll a feared batter most pitchers don't want to face him."

从它的例句中可以看出，独立的两个句子用","来连接了。那也就是说我以前的理解是错误的了。

真的是颠覆呀。