Females account for 65% of sales at a major retailer. Assume the probability of a customer being female is .65. The probability that a purchase made by a female exceeds $100 is .32 and the probability that a purchase made by a male exceeds $100 is .6. Suppose the manager is told that a customer made a purchase in excess of $100. What is the probability the customer was a female?

a. 0.65

b. 0.91

c. 0.09

d. 0.21