For a Given Confidence Level and Sample Size, Which of the Following

Multiple Choice

For a given confidence level and sample size, which of the following is true in the interval estimation of the population mean when σ is known?

A) If the sample standard deviation is smaller, the interval is wider.
B) If the population standard deviation is greater, the interval is wider.
C) If the population standard deviation is smaller, the interval is wider.
D) If the population standard deviation is greater, the interval is narrower.