A Researcher Introduces a New Mathematics Program in One School

A researcher introduces a new mathematics program in one school district and uses a neighboring district as a no-treatment control group.After the program is in place for 6 months,the researcher intends to give the students in both districts a standardized mathematics test and then compare their scores.This research cannot be classified as a true experiment because

A) the treatment is administered to only one group.
B) there is no pretest to determine mathematics ability before the program.
C) the researcher does not control the assignment of participants to groups and therefore has a nonequivalent groups design.
D) it is not conducted in a laboratory.