A medical researcher wishes to determine if there is a relationship between the number of prescriptions written by pediatricians and the ages of the children for whom the prescriptions are written. She surveys all the pediatricians in a geographical region to collect her data. What is the response variable?
◦ Number of prescriptions written
◦ Age of the children for whom prescriptions were written
◦ Number of children for whom prescriptions were written
◦ Pediatricians surveyed