Which of the Following Is a Weakness of a Posttest-Only

Multiple Choice

Which of the following is a weakness of a posttest-only control group design?

A) Researchers have limited information available about group equivalence prior to treatment.
B) It is expensive to the researcher in terms of time and effort.
C) Confidentiality of the responses is compromised as the participants are unable to respond anonymously.
D) Repeated testing may be occasionally bothersome to some participants.