What Is the 95% Confidence Interval for the Standard Deviation $0.8 < \sigma < 2.1$

Multiple Choice

What is the 95% confidence interval for the standard deviation of birth weights at County General Hospital, if the standard deviation of the last 25 babies born there was
1) 1 pounds?

A) $0.8 < \sigma < 2.1$
B) $0.9 < \sigma < 1.5$
C) $0.8 < \sigma < 1.9$
D) $0.7 < \sigma < 2.3$