Evaluate the expression. If the answer is not an integer, round to four decimal places. 31 4 45 4 Select the correct factorial formula below and, if necessary, fill in the answer boxes to complete your choice. n! O A. The factorial formula for n Ck = : therefore 31 C4 = and 45 4 = n! O B. The factorial formula for Ck = ( n - k ) ! therefore 31 4 and 45 4 = n! O C. The factorial formula for nk = kl(n - k)! therefore 31 4 and 45 4 =