1. Oberlin College in Ohio was a renegade institution at its 1833 founding for deciding to accept both men and women as students.

(A) at its 1833 founding for deciding to accept

(B) for the decision at its 1833 founding to accept

(C) when it was founded in 1833 for its decision to accept

(D) in deciding at its founding in 1833 to accept（D）

(E) by deciding at its founding in 1833 on the acceptance of

为什么是这个答案？什么意思？

I also chose C  originally.

I think C is wrong because the college was  a renegade institution not only when it was founded. It was a regenagde institution 体现在 deciding ...

Meanwhile, it gave the wrong impression that there were multiple foundings, and the founding in 1833 was just one of them.