Final answer:
A white blood cell (WBC) count of 2000 mm3 is indicative of leukopenia, a condition where too few leukocytes are produced. This weakens the immune system and increases the risk of disease.
Step-by-step explanation:
The white blood cell (WBC) count of 2000 mm3 indicates leukopenia, which is a condition characterized by too few leukocytes being produced. This condition can make the individual unable to ward off diseases, as the immune system is weakened. Although excessive leukocyte proliferation, known as leukocytosis, can occur in response to infection, the low WBC count in this case suggests leukopenia.