Derrick Is Conducting a Stratified Sampling Procedure

Derrick is conducting a stratified sampling procedure. He wants to assure he has the appropriate representation of students from at each of the class levels in his study. Next he will

A) identify and define the population.
B) determine desired sample size.
C) classify all members of the population as members of the subgroups.
D) randomly select an appropriate number of individuals to represent the subgroups.