Answer:
Lacks random assignment
Explanation:
the researcher may not Be able to establish valid causal relationships as the study lacks random assignment in that participants do not get equal opportunity of being assigned to groups. Random assignment means the researcher applies chance in assigning participants to groups such that the study is not biased and causal relationships are not affected. For example if a participant does not get to choose his group, the researcher randomly flips a coin to assign him to a group and so there is an uncorrupted result in findings
Answer:
so sorry I didn't help you but I really don't know the answer of this question and I did this because I did assembly point so that I can question one question from someone that's why I really sorry and thank you for free points
