CR-Professor: In an effort to combat stagnating revenues...

[CHUNX638]

Professor: In an effort to combat stagnating revenues, an apparel company launched a special six-month advertising campaign, purchasing fifty percent of the poster space on the subway trains of ten major cities. The tactic was risky due to the large outlay of funds required, but the results demonstrate that the campaign was a resounding success. During the months of the campaign, sales climbed to record levels, and the company had the number one ranking in market share.

The answer to which of the following would be most useful in evaluating the professor's argument?

A.What percent of subway riders were aware of the apparel company prior to the campaign?
B. How profitable was the company during the months of the campaign?
C. Were revenues throughout the apparel industry stagnant in the months prior to the campaign?
D.Did any of the company’s divisions experience a significant reduction in sales?
E.At the time of the campaign, did the company significantly increase spending on other forms of marketing?

I have trouble in identifying this argument's conclusion.
In my opinion, the conclusion is "the results demonstrate that the campaign was a resounding success". But I fail to definite "success" in this argument. According to the first sentence, I know the apparel company launch advertising campaign in order to increase revenues. So I think the success is just to combat stagnating revenues instead of improving profits, right?

And I have some questions about answer E.
The explanation: If the company increased spending on other forms of marketing, then perhaps the subway advertising campaign was not the cause of the sales success described in the argument.
Why increasing spending on other forms of marketing will improving the company's sales? I think E conclude too much, maybe because the labor cost increase or something else.

Thank you very much!

[Sage Pearce-Higgins]

You're right in your identification of the conclusion. The Professor claims that the campaign was a "success". Sure, this is a little bit vague, but it's reasonable to understand this as meaning that the campaign caused the company's revenues to increase. The final sentence gives some evidence to support the conclusion.

I know GMAT arguments well, and as I read an argument like this, I respond by asking questions and recognizing patterns. Sure, we know that the sales increased after the campaign, but there seems to be a gap - did the sales increase because of the campaign? This is a famous logical flaw called correlation-causation. Take a look at this: https://www.khanacademy.org/partner-con ... -causation

So, it's a good idea to think about other things that might have caused the high revenue. Perhaps they just launched a great new product, or perhaps they had a viral marketing campaign or perhaps they increased their prices. It would be useful to know what other actions took place at the same time as the campaign. This is what answer E does: if the company spent lots of money on other forms or marketing, then perhaps the recent revenue success was because of the other marketing, not the campaign that the professor mentions. Generally, it's safe to assume that companies spend money on marketing in order to increase their sales.

Of course, we don't know any of these things for sure, we're just thinking of possibilities, but that's what the problem is asking us. We need to find something that is "useful" to help "evaluate" the argument, i.e. something that might impact whether the professor is correct in his conclusion.