Final answer:
The population standard deviation is found by taking the square root of the variance. Given a variance of 9, the standard deviation is 3.
Step-by-step explanation:
The question is asking to find the population standard deviation given a population variance. In statistics, the variance (σ²) is the square of the standard deviation (σ), which is a measure of the spread of scores within a data set.
To find the standard deviation, we take the square root of the variance. Given that the variance (σ²) is 9, the population standard deviation (σ) would be √9. Therefore, the population standard deviation is 3.
Answer: The population standard deviation is c. 3.