A random sample of 49 statistics examinations was taken. The average score, in the sample, was 84 with a variance of 12.25. The 95% confidence interval for the average examination score of the population of the examinations is:
a. 76.00 to 84.00
b. 77.40 to 86.60
c. 83.00 to 85.00
d. 68.00 to 100.00