Explanation

Under GIPS (Global Investment Performance Standards), composites must include all actual, fee-paying, discretionary portfolios managed in accordance with the stated investment objective, strategy, or mandate.

Key points:

1. Discretionary requirement: Only discretionary accounts (where the firm has full discretion over investment decisions) should be included in composites. Non-discretionary accounts should be excluded.
2. Fee-paying requirement: Composites should include fee-paying accounts. Non-fee-paying accounts should be excluded unless the firm chooses to include them, but they must be clearly identified.
3. Retail vs. institutional: GIPS does not require separate composites based on client type (retail vs. institutional). A retail account can be included in a composite with institutional accounts as long as they share the same investment mandate.

Therefore, a retail client's account would most likely be in a composite composed of discretionary accounts (Option B), not necessarily restricted to retail accounts (Option A) or containing both fee-paying and non-fee-paying accounts (Option C).