D tells us that the assumption is that traffic control tapes aren't accurate. It seems from the argument that the main concern is that it was a partial review, so it wasn't very thorough. The airport administrator highlighted that the other source was documented and required from ALL commercial flights, so it's more extensive.
B is the correct answer because the administrator is overlooking a crucial flaw: the flight reports are done by pilots. Pilots are the very people who would be at fault if the planes veered off course. It is human nature to underreport our own failings. Therefore, the reports on which the administrator is relying are likely somewhat less trustworthy than they seem to believe.
willsMay 24, 2019
I don't understand why E is wrong. Wouldn't the fact that the figure that the opponents are using is unreliable compared to the figure the administrator uses mean that there is a lack of conclusive evidence? And wouldn't the conclusion that the opponents are wrong mean that the administrator is inferring that the opponents' statements are inaccurate?
RaviMay 24, 2019
@wills,
Happy to help. Let's take a look at (E). As noted in the question stem, we're looking for the answer that describes a flaw in the argument.
(E) says, "The argument infers from a lack of conclusive evidence supporting the higher number's accuracy that it must be inaccurate."
(E) is tempting, but the argument does not make the conclusion that the higher number is inaccurate in absolute terms. Rather, the argument concludes that it is relatively unreliable compared to the other figure. This is far less extreme than saying it's absolutely inaccurate, so this is why (E) is out.
Does this make sense? Let us know if you have any other questions!
