Refer to the Current Allergy & Clinical Immunology (March 2004) study of latex allergy in health care workers. There is a claim that the mean number of latex gloves used per day by all hospital employees is less than 20 gloves. A sample of 46 were selected with a mean number of latex gloves used per day by all hospital employees of 19.3 and standard deviation of 11.9. Assume alpha is 0.01.

What is the rejection region?
a. z<-2.575
b. z<-2.33
c. z >2.575
d. z>2.33