Final answer:
The normal adult white blood cell range for a healthy individual is (A) 3.8-10.8 thousand cells per microliter (thousand/mcl), which is option A.
Step-by-step explanation:
The normal adult white blood cell (WBC) range is frequently used to gauge a person's immune system status and detect potential health issues. Looking at the information provided: 'The absolute number of white blood cells generally considered “healthy” ranges from 3.5 to 11 x 10⁹ cells/L,' when translated to the common clinical measurement in the United States (thousands per microliter or μls/mcl), aligns closely with one of the provided options.
Taking into account the conversion factor that 1 L = 1,000 μl, the 'healthy' range would be 3.5 to 11.0 thous/μl, which, when rounded, would match the range given in option A: 3.8-10.8 thous/mcl. This is consistent with the provided reference ranges for primates which include humans, stating the range from 4,800 to 10,800 cells per μl. Therefore, the correct answer to the student's question is A: 3.8-10.8 thous/mcl.