Answer: The level of risk reduction provided by the portfolio.

**Explanation:** - **Option A** is incorrect because the expected return of an equally weighted portfolio is determined by the weighted average of the individual asset returns and is not influenced by the correlations between the assets. - **Option B** is incorrect because the standard deviation of an equally weighted portfolio is affected by the correlations between the assets. An increase in correlation leads to an increase in the portfolio's standard deviation, not a decrease. The formula for the standard deviation of a two-asset portfolio, for example, shows that higher correlation increases the portfolio's risk. - **Option C** is correct because higher correlations between asset returns reduce the diversification benefits of the portfolio. Diversification relies on combining assets whose returns do not move perfectly together. As correlations increase, the effectiveness of risk reduction diminishes, especially during periods of market stress when correlations tend to rise.

Author: LeetQuiz Editorial Team