Answer: The correlation coefficient ranges from 0 to +1

The correct answer is C because the correlation coefficient actually ranges from -1 to +1, not from 0 to +1. **Explanation:** - **Option A is true:** The correlation coefficient (typically Pearson's correlation coefficient) measures the strength and direction of the linear relationship between two random variables. - **Option B is true:** The correlation coefficient is a dimensionless quantity with no units, as it's calculated by standardizing the covariance by the product of the standard deviations of the two variables. - **Option C is NOT true:** The correlation coefficient ranges from -1 to +1, not from 0 to +1. A value of -1 indicates perfect negative correlation, 0 indicates no linear correlation, and +1 indicates perfect positive correlation. - **Option D is true:** Random variables with a correlation of +1 are indeed said to be perfectly correlated, meaning they move in exactly the same direction in a perfectly linear relationship. In finance, the correlation coefficient is crucial for portfolio diversification, risk management, and understanding how different assets move relative to each other. The fact that it ranges from -1 to +1 allows investors to identify assets that might provide diversification benefits (negative correlation) versus those that move together (positive correlation).

Author: Nikitesh Somanthe