To cast doubt on this claim, we need to show evidence that Alpha Cola was already more popular than Epsilon Cola before the ad campaign.
(A) Alpha Cola’s recent ad campaign was intended in part to increase sales of the soft drink to soda drinkers aged 18 to 25.
This tells us about intent, not what was happening before the campaign => eliminate.
(B) Beverage buying decisions can be significantly influenced with effective ad campaigns.
It doesn’t tell us what Alpha’s status was before the campaign => eliminate.
(C) Alpha Cola’s recent advertising campaign was one of the most expensive advertising campaigns in history.
This emphasizes the size of the campaign but doesn’t refute Epsilon’s claim about Alpha’s previous popularity => eliminate
(D) Prior to the recent campaign, Alpha Cola had never advertised but had significantly outsold all other soft drinks on the market for several years.
If Alpha Cola was already outselling other soft drinks (including Epsilon) without any advertising, it suggests Alpha’s popularity wasn’t just due to the recent campaign. This casts doubt on the assertion made by Epsilon.
(E) Most people prefer the taste of Epsilon Cola to that of Alpha Cola.
This strengthens Epsilon's case => eliminate
Correct answer: (D)