As astutely pointed out by Anne in her comment, the “correct” answer to the recertification question was #4, trimethoprim-sulfamethoxazole, for the following reason:
I am not a doctor, I am a test developer. Having exactly zero knowledge about the content here (could be Chinese to me), but based solely on the structural design of multiple-choice items, I would venture to guess that the correct answer (the “key” in testing parlance) is #4. I say this merely because it is significantly longer than the other three options (the “distractors”) and therefore leads one to believe that it contains the best information.
However, what does it mean that the person giving the correct answer isn’t a doctor, and admittedly has “zero knowledge” on the subject?
Well, it probably means that the question is flawed — which is obviously the case, since there’s no right answer.
Azithromycin is plainly wrong.
You migh choose dicloxacilln or cephalexin, but one over the other? And both don’t cover MRSA.
And trimethoprim-sulfamethoxazole doesn’t cover strep.
Don’t believe me? Read this recent paper on community acquired “nonculturable” cellulitis, which shows that a significant proportion are not surprisingly still due to beta strep, even in the era of community acquired MRSA.
In the real world of treating patients and not answering test questions, what we actually should do in this situation is hardly clear — diclox or cephalexin first then change if no response? TMP-SMX + amox?
I’d suggest that such ambiguous situations make for exam items that are more maddening than educational.