Calculating the Effect Size with Single-System Data Involves

Calculating the effect size with single-system data involves:

A) Calculating the standard deviation of the intervention data and then dividing that into the standard deviation of the baseline data.
B) Calculating the standard deviation of the baseline data and then dividing that into the intervention mean.
C) Treating the baseline data like a control group.
D) Calculating the baseline mean and then dividing that into the intervention mean.