Virginia Code § 38.2-5205 mandates that long-term care (LTC) policies define pre-existing conditions, typically as conditions for which medical advice or treatment was recommended or received within six months before the policy’s effective date. Option B (pre-existing condition) matches this definition exactly, as it identifies prior health issues that may affect coverage (e.g., exclusions or waiting periods). Option A (covered illness) is vague and implies a condition already insured, not necessarily pre-existing. Option C (long-term care condition) isn’t a standard term; LTC policies cover specific needs (e.g., ADLs), not a category tied to this timeframe. Option D (pre-determined risk) suggests underwriting factors, not a specific medical history definition. The study guide likely details this six-month lookback as a common LTC standard, with examples like a recent stroke diagnosis, emphasizing disclosure requirements and potential coverage limits, confirming B as the answer.