Answer:
a. Missy
Explanation:
The z-score is how manu standard deviations a measure of normally distributed random variable is above or below the mean.
A negative z-score indicates that the measure is below the mean.
A positive z-score indicates the measure is above the mean.
In this problem, we have that:
Missy has a higher z-score than Frank. This means that he had a better relative score on her exam than Frank
So the correct answer is:
a. Missy