For the last six months, because of concern over an increase in the use of dangerous substances to improve performance, athletes in the Worldwide Sports League have been forbidden by league officials to use fasterol, a reflex-enhancing substance known to cause serious health problems after long-term use. Despite the ban, a higher percentage of athletes in the league have tested positive for the substance during chemical screenings in the last six months than in any prior six-month period since the league initiated testing. Clearly, the attempt to prohibit the use of fasterol merely increased the use of the substance by athletes in the league since the ban.

The answer to which of the following questions would be LEAST useful in evaluating the validity of the claim made in the argument above?

A) For how long after use does a residue of fasterol remain in an athlete's body?
B) Have athletes in the league experienced a decreased incidence of the types of health problems caused by fasterol?
C) Do any other performance-enhancing substances possess chemical characteristics similar to those of fasterol?
D) Was the chemical screening by which athletes were screened for fasterol in the last six months the same as that used prior to the prohibition?
E) Have the producers of fasterol recently increased their marketing efforts?


OA B

Source: Princeton Review