KAPLAN OFFICIAL EXPLANATION(A) Strengthen the Argument
A valid strengthener must make the conclusion more likely to follow from the evidence.
A warning to consumers: apparently, extended warranties on electronic items are a waste of money. Consumers don’t need to purchase extended warranties because according to the author, most problems with electronics occur during the period covered by the manufacturer’s warranty. But that isn’t when all problems occur, just most problems. For the argument to hold, the author must be assuming that the few problems that occur after the warranty expires do not justify the cost of the extended warranties. Choice
(A) is supports this assumption, and thereby strengthens the author’s argument: if post-warranty problems are inexpensive to fix, then we are better off not buying extended warranties.
(B) does involve the cost of warranties, but the author here is interested in the cost of warranties relative to that of fixing electronics goods without a warranty. Besides, if extended warranties are “generally inexpensive,” that doesn’t strengthen the idea that consumers are better off not buying them.
(C) states that consumers purchase extended warranties because “special circumstances” make their items more likely than usual to break. However, we don’t know when these “special circumstances” kick in, so it’s not clear what, if any, effect they have on the argument.
(D) deals with how far the warranties extend. The “subsequent years” for which the extended warranties cover certain products can’t strengthen or weaken the argument, since the argument’s soundness depends on the relative cost of the warranties.
(E) provides a reason why the retailers would sell the warranties – to increase sales. This has little bearing on whether the warranties are good deal for the consumers.