Understanding the argument -
Wipla Pharmas has come up with a new vaccine for Valian Flu, a very common ailment in the city of Croone. - Fact
The vaccine has 80% fewer side effects than the currently widely used vaccine marketed by Wipla’s chief competitor, Hoopla Pharmas but Wipla’s vaccine is costlier. - Fact
The medical fraternity is all set to bring about a discontinuation in the use of vaccines that have more than five cited side effects in the next year or so. - Fact
Hoopla’s current vaccine has at least 15 cited side effects and Hoopla is unlikely to come up with a new vaccine with less than 5 side effects in the next year or so. - Fact
Therefore, once the discontinuation in the use of vaccines with more than 5 side effects becomes effective, Wipla’s vaccine should register good sales after that. - Conclusion.
Option Elimination - Assumption
A. The Valian Flu afflicts a significant proportion of the population every year. - We already know from the passage. Distortion.
B. Wipla R & D department is working on identifying a cheaper method of producing the vaccines on a large scale. - "a cheaper method of producing the vaccines" is out of scope.
C. The other vaccine producing pharmaceutical companies in Croone have not been able to come up with a vaccine that is comparable to Wipla’s. - ok
D. People will be as willing to try out Wipla’s vaccine as they have been to try out Hoopla’s vaccine. - "people's willingness" is out of scope.
E. Most people will not find the price of Wipla’s vaccine a big deterrent in the way of using it. - Lets negate it
Most people will find the price of Wipla’s vaccine a big deterrent - ok. So if there is no alternative, people still have to buy it and the sales will increase.
Even if there are other competitors, say they are 20% more expensive than Wipla, customers will still buy Wipla and sales will increase.
Only in cases there are alternatives and those alternatives are cheaper than, Wipla's sales may not grow. So there are a lot of assumptions required to make this correct. Distrotion.