Professor russel wants to examine the effectiveness of his new reading instruction method for third graders. he locates two third grade classes in the same school. he assesses all students' current reading ability at the start of the school year. he then has one classroom utilize his new instruction method while the other classroom uses the traditional method. at the end of the school year, professor russell assesses reading ability once again and compares group differences. the design of this study exemplifies which of the following?
a. nonequivalent control group design.
b. static group comparison.
c. solomon two group design.
d. factorial design.