A Large Company That Produces a "Fat-Burner" Pill Claims an Average

Multiple Choice

A large company that produces a "fat-burner" pill claims an average loss of 20 pounds in the first month. A consumer advocacy group believes that this claim is actually just "hype" intended to sell more of the compound. The advocacy group would like to obtain statistical evidence about this issue and takes a random sample of 100 consumers who responded that they had purchased the pill but didn't know what the survey was about. They find that these 100 people lost an average of 18 pounds with a standard deviation of 7.5 pounds.
What is the value of the standardized test statistic for this significance test?

A) -2.000
B) 0.267
C) -0.267
D) -2.667