Bank of New York would like to test the hypothesis that the average checking account balance for younger customers (under 40 years old) is different from the average checking account balance for older customers (40 or more years old). The following data summarizes the sample statistics of the checking account balances for customers in each age group. Assume that the population variances are unequal. Younger Older Sample mean $1,150 $1,230 Sample size 16 14 Sample standard deviation $100 $70 Let Population 1 be defined as younger customers and Population 2 as older customers. Determine the degrees of freedom for the test. A. 14 B. 15 C. 26 D. 27