Which of the Following Statements Is/are True About Carrying Out

Multiple Choice

Which of the following statements is/are true about carrying out experiments and quasi-experiments in social agencies

A) The intervention being tested might not be implemented in the intended fashion.
B) The control condition might be contaminated by interaction between clients in the experimental and control groups.
C) Practitioners might violate the research protocol for case assignment to make sure that clients receive the intervention being evaluated.
D) Reluctance by outside agencies to refer clients might hinder obtaining a sufficient sample size.
E) All of these.