Which factors are risk factors for Chronic Lymphocytic Leukemia (CLL)?

• A. Increasing age only
• B. Exposure to Agent Orange only
• C. Increasing age and exposure to Agent Orange
• D. Family history of leukemia only

Answer: (C)

The key idea is that risk for Chronic Lymphocytic Leukemia rises with age and can be influenced by certain environmental exposures. Aging is the strongest and most consistent risk factor, with most cases occurring in older adults. Exposure to Agent Orange has been linked, in several studies, to a higher risk of CLL, though the evidence is observational and not uniformly conclusive. So the option that includes both increasing age and Agent Orange exposure best matches the factors that can contribute to CLL risk. While family history can also play a role, it’s not as clearly tied to the age-related pattern and environmental exposure highlighted here, so including both age and Agent Orange exposure provides the most accurate combination among the choices.