Answer:
d. Posttest-only design with nonequivalent groups
Explanation:
Nora is interested in differences in amount of content retained from a lecture based on time of class. She compares her two sections. Section A meets at 8 am and Section B meets at 2 pm. She tests students in both sections, unannounced, on content that she taught two weeks ago. Posttest-only design with nonequivalent groups is what Nora was illustrating