The argument tells us that according to the poll conducted on the eve of the election, more voters said they favored Panitch than stated that they favored any other candidate. In the end, another candidate defeated Panitch. The question asks us to identify an answer choice that fails to resolve this discrepancy. We could think of many explanations why this could have happened - perhaps, the poll was not representative or something happened between the eve of the election and election day.
(B) tells us that a third candidate, Mulhern, conducted a press conference on the morning of the election and withdrew from the race. This fact helps explain the discrepancy because it would suggest that voters who supported Mulhern switched their vote to another candidate, in this case Yeung, resulting in him winning the election despite the prior day poll results.
Let me know if this helps and if you have any further questions.
