The average age of applicants for a new job is 31, with a standard deviation of 8. The hiring manager is only willing to accept applications whose age is within one standard deviation of the average age. What is the maximum number of different ages of the applicants? Choose the correct option
A) 8
B) 14
C) 15
D) 17
E) 30

Rationale: "within one standard deviation of the average age means 31 + / - 7 23 - - 31 - - 39 number of dif . ages - 23 24 25 26 27 28 29 30 31 32 33 34 35 36 37 38 39 total = 17 d"
Answer: D