A child psychologist wanted to determine if the babies responded to their mothers voice when they could not see them. She measured the total time the babies actively sucked their pacifiers while...

A child psychologist wanted to determine if the babies responded to their mothers voice when they could not see them. She measured the total time the babies actively sucked their pacifiers while listening to their mothers' voices without seeing them for 10 minutes. She ran this test on 12 babies and found the average time was 4.8 minutes with a standard deviation of 1.1 minutes. What one is the correct 90% confidence interval for the average amount of time the babies sucked their pacifiers that can be obtained from this data? (Assume that the times are approximately Normally distributed)
A. (4.230, 5.370)
B. (4.178, 5.422)
C. (4.278, 5.322)
D. (4.101, 5.499)