Cohen Proposed Effect-Size Conventions Based on the Effects Observed in Psychology

Multiple Choice

Cohen proposed effect-size conventions based on the effects observed in psychology research in general because

A) experimenters need to assess whether the obtained effect size will allow them to reject the null hypothesis.
B) determining how large an effect can be expected in a given experiment is difficult.
C) they follow from the original scales he developed.
D) they are more accurate than calculating a minimum meaningful difference.