If there is an election, you can either vote or not. If you vote, you have the satisfaction of knowing you influenced...

Emil-Kunkin on October 5 at 12:25AM

Hi, the initial argument starts out by telling us that if something happens, then one of two outcomes will happen, bc then gives us a necessary conclusion for each of those two outcomes.

In other words
If E then A or B
If a then x
If b then z

In b however, we never do anything with the second possibility, the B.

It goes
If w then r or n
If r then s or c

To match the original passage we need to do something more with N, which b does not do.