Find the 95% Confidence Interval for the Variance of the Heights

Multiple Choice

Find the 95% confidence interval for the variance of the heights of maple trees if a sample of 12 trees has a standard deviation of 10 feet.

A) $11.0 < \sigma ^ { 2 } < 9.0$
B) $7.0 < \sigma ^ { 2 } < 17.5$
C) $89.0 < \sigma ^ { 2 } < 111.0$
D) $48.8 < \sigma ^ { 2 } < 308.0$