Which of the Following Has Been Found Regarding the Use

Which of the following has been found regarding the use of observational methods to study sexual communication and conflict?

A) Couples who participate in observational studies often report being unhappy afterward.
B) Couples who participate in observational studies often report that the experience benefitted their relationship.
C) Couples are more likely to confuse researchers with socially desirable responding when an observational method is used than when self-report is used.
D) Couples who participate in observational studies tend to be couples who are less concerned about being open about their sexual conflicts and less concerned about "the outside world" knowing what takes place during discussions, which may mean the sample is biased.