The ASQ (American Society for Quality) Regularly Conducts a Salary

The ASQ (American Society for Quality) regularly conducts a salary survey of its Membership, primarily quality management professionals.Based on the most recently Published mean and standard deviation, a quality control specialist calculated the z-score Associated with his own salary and found it was -2.50.This tells him that his salary is

A) 2 and a half times more than the average salary.
B) 2 and a half times less than the average salary.
C) is 2.5 standard deviations above the average salary.
D) is 2.5 standard deviations below the average salary.
E) much higher than the average salary.