Matt is participating in a two-day experiment. On Day 1, he takes a memory test after running on a treadmill for 2 minutes. On Day 2, he takes a similar test after running for 10 minutes. The...

Matt is participating in a two-day experiment. On Day 1, he takes a memory test after running on a treadmill for 2 minutes. On Day 2, he takes a similar test after running for 10 minutes. The experimenters plan to compare Matt’s performance on the two tests. This sounds like a

a. within-subjects design.

b. double-blind control.

c. between-subjects design.

d. correlational design.