Business analyst: Since many air travellers choose flights on the basi

­Business analyst: Since many air travelers choose flights on the basi­s of fares posted online, Skyways Airlines now charges for many formerly complimentary services. Since these charges are not included in posted fares, the fares are lower, making the flights appear cheaper to customers shopping online. However, Skyways' strategy will inevitably backfire. Customers facing unexpected charges on flights will resent the airline and turn to its competitors.

The conclusion of the argument is the following:

Skyways' strategy will inevitably backfire. Customers facing unexpected charges on flights will resent the airline and turn to its competitors.

We see that the business analyst has reasoned that, since the total cost of the airfare and formerly complimentary services is higher than the fares customers see online, customers will be surprised by the charges for the services and therefore resent the airline and go to competitors.

How this argument works is a little vague, in that it doesn't directly say in the premises that the charges are unexpected. Rather, it first implies that the charges are unexpected by saying that, by not including them in posted fares, the airline makes the fares "appear cheaper" and then in the conclusion jumps to calling them "unexpected charges." So, the line between evidence and conclusion is blurred a little. Still, by using process of elimination and seeing which choice works best, we can arrive at the correct answer.

Which of the following is an assumption the business analyst's argument requires?

This correct answer will be something that must be true for the conclusion to follow from the facts presented.

A. At least some of Skyways Airlines' competitors charge separately for one or more formerly complimentary services.

This choice weakens the argument rather than states an assumption necessary for the argument to work.

After all, if competitors also charge separately for formerly complimentary services, then it's likely that either Skyways' customers won't turn to competitors because of Skyways' charges or, if customers do resent such charges, competitors' customers will resent them too and turn to Skyways'. In any case, if this choice is true, then we have less reason to believe that the strategy will backfire.

Eliminate.

B. When unexpected charges for services are included, the average cost of flights on Skyways Airlines is higher than that on most competing airlines.

This choice is trickiy because it helps to support the conclusion. After all, if this choice is true, then we have more reason to believe that Skyways' customers will go to competitors since the customers can get a better deal by going to competitors.

At the same time, we aren't looking for a strengthener. We need an assumption, and it's not the case that this choice must be true for the argument to work.

After all, resentment from unexpected charges could be enough to cause Skyways' customers to turn to competitors. So, Skyways' customers could turn to competitors even if the cost of flights on Skyways is not higher than that of flights on competing airlines. 

So, the argument works even if it's not true that the average cost of flights on Skyways Airlines is higher than that of flights on competing airlines.

Eliminate.

C. If Skyways Airlines did not charge separately for formerly complimentary services, few customers would resent the airline or turn to its competitors.

The argument is about what will happen because of Skyways charging for formerly complimentary services.

The support for the conclusion doesn't require this assumption about what would not happen.

After all, even if more than a few customers would resent the airline if it did not charge for complimentary services, it could still be the case that charging for such services would cause some customers to resent the airline.

Eliminate.

D. At least some customers who buy Skyways Airlines' tickets incorrectly assume that the fares include certain complimentary services.

This choice is interesting.

After all, if this choice is not true and no customers who buy Skyways Airlines' tickets incorrectly assume that the fares include certain complimentary services, then Skyways' customers will not resent the airline and turn to competitors because of unexpected charges because the charges won't be unexpected. In that case, the conclusion doesn't follow from the facts.

So, this choice is an assumption the argument requires.

Keep.

E. An airline's business strategy will backfire only if it causes most customers to resent the airline and turn to its competitors.­

This choice doesn't have to be true for the argument to work.

After all, the strategy could backfire by causing resentment even if causing resentment is not the only way it can backfire. After all, the fact that a strategy could backfire in other ways doesn't mean that it won't backfire in a resentment-causing way.

Eliminate.

Correct answer: D