Use the Following Identify Whether Each of the Following Scenarios Describe a Randomized

Use the following
Identify whether each of the following scenarios describe a randomized comparative experiment or a matched pairs experiment.
-To study the effect of classical music on concentration, 26 math majors were assigned at random into two groups. Subjects in one group listened to classical music while trying to solve a hard Sudoku puzzle, while the subjects in the other group solved the same puzzle in a silent room. The time it took each student to finish was recorded.