Final answer:
The best indicator that a patient with cellulitis is recovering is a white blood cell count that falls within the normal range. Therefore, A. WBC of 8200/μl is the best indicator among the provided options.
Step-by-step explanation:
In assessing the recovery of a patient with cellulitis, the best laboratory indicator would be to look at the white blood cell (WBC) count. An elevated WBC count can indicate an active infection, and a return to a normal WBC range, which is typically between 4,500 and 11,000 cells per microliter, would suggest recovery. Therefore, the answer is A. WBC of 8200/μl as it falls within the normal range, unlike the other options which indicate either leukocytosis (C and D) or leukopenia (B), both of which are abnormal and indicative of potential ongoing issues.