I guess the stimulus is trying to say that low-fare airlines don't have reliable records while big airlines do, which leads to the conclusion that big airlines are safer. But what if reliable records don't equal safer? What if the record says that the big airline is not safe? Choice A is trying (but not solid) to say that the big airlines are not safer than low-fare airlines, it is trying to attack the conclusion rather than attacking the link between premises and conclusion.

Hi Chris, thanks very much for your talk today. I have to leave early because of another scheduled meeting. Can I ask where we can have the record of your talk especially the Q&A part?