A Researcher Wants to Study a Drug Use Prevention Program

A researcher wants to study a drug use prevention program targeted at high school freshmen in Chicago. The student population is around 200,000 and is extremely diverse with respect to race, ethnicity, and socio-economic status. The researcher makes a list of all the high school freshmen in the city and randomly draws 100 names from the list. The bias in this sampling plan is best described as:

A) random sampling error.
B) selection bias.
C) discrimination.
D) error.