PT 12 S1 Q14

Morris High School has introduced a policy designed to improve the working ... ...

The argument's reasoning is questionable because the argument fails to rule out the possibility that
(A) before the new policy was instituted, more part-time than full-time teachers at Morris High School used to quit during their first year
(B) ...
(C) ...
(D) ...
(E) ...

*This question is included in Flawed Reasoning: Intro Set