Human blood pressure levels are normally distributed. if you measured an individual's blood pressure and found the blood pressure level to have a z-score of 2.1, what would you conclude about that person?

a. the individual's blood pressure is unusually high, compared to others.
b. the individual's blood pressure is 2.1 times higher than the average person.
c. the individual's blood pressure level is about average, compared to others.
d. since the z-score is positive we know that the individual has normal blood pressure, compared to others.