In a poll conducted by interviewing eligible voters in their homes

With these paradox/discrepancy questions, the most important thing to do is to identify the paradox before you move to the answer choices. Often times you can then start to anticipate what kind of answer you'll need. Here, the discrepancy is:

1) The polls strongly favored Kenner...just hours before the election
2) But Muratori won

How could those two things be true together? Here, I'd start to anticipate some things that could have made that difference. Maybe Kenner had to withdraw from the election the night before? Or some kind of stunning news came out that ruined Kenner's candidacy? Or maybe those voters who preferred Kenner just didn't actually go out and vote, whereas those that preferred Muratori made sure to go vote.

Choice E hits on that last point - it shows why, even though most people preferred Kenner, those people didn't care enough about the election to take the time to go vote their preference, while those who preferred Muratori came out in greater force. Choice E explains the discrepancy - "prefers" doesn't necessarily mean "voted for".

If you look at D, D doesn't directly tie into the candidates (we don't know that younger voters would have preferred Muratori, so we can't say that lowering the voting age would have played a role), but more importantly the time-stamp on it proves that it's irrelevant. The polls were taken YESTERDAY so they should have been inclusive of the voting population at that time. D deals with six months ago, so it shouldn't have any bearing on the discrepancy that took place from yesterday to today.