IMO A.
Premise 1: Patients will lose body fat
Premise 2: Patients will also lose lean body mass (defined as everything that isn't fat)
A: Takes into account both premises and recognizes that percentage of body fat may remain unchanged even if person loses fat. (Absolutes vs. Percentages)
B: People will lose weight if they take the drug.
C: Also a contender, but the chemicals in the drug are beyond the scope of the question...IMO
D: Exercise is never discussed and hence beyond the scope of the question
E: This is largely an assumption because what catalyzes the loss of body fat and lean muscle is never discussed and also beyond the scope of the qeusiton
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