Four Sorority Sisters Took General Psychology, but They Were Enrolled $\mu$

Four sorority sisters took General Psychology, but they were enrolled in different sections that were taught by different instructors who gave different tests. After the first test, they gathered at the sorority house with their own scores and the class parameters. Which sister did best?

A) Lisa, 14 $\mu$ = 10, $\sigma$ = 3
B) Vickie, 25 $\mu$ = 20, $\sigma$ = 10
C) Merry, 90 $\mu$ = 95, $\sigma$ = 3
D) Stacey, 100 $\mu$ = 70, $\sigma$ = 20