Which of the Following Is an Example of a One-Group

Which of the following is an example of a one-group pre-test post-test experimental design?

A) Store traffic is measured following the announcement of a clearance sale
B) Store traffic is measured; a sale is announced; store traffic is measured again
C) People who saw an ad are compared to people who didn't see the ad on their attitude toward the brand
D) Random assignment is used to divide participants into the control and experimental groups; a control group responds to a pre-test on brand preferences and a post-test; an experimental group responds to a pre-test, is exposed to a commercial for the brand, and responds to a post-test
E) Random assignment is used to divide participants into control and experimental groups; the experimental group is exposed to a commercial and then attitude toward the brand is measured; attitude toward the brand is also measured for the control group