Which of the following statements is true about the benefits of random assignment?
Answer
A
The variability between each subject would be evenly distributed between the two groups, so any observed differences in the level of irritation between the two groups are more likely due to the new cream.
B
The variability between each subject may not be evenly distributed between the two groups, so any observed differences in the level of irritation between the two groups may or may not be due to the new cream.
C
The variability between each subject may not be evenly distributed between the two groups, so any observed differences in the level of irritation between the two groups would not be due to the new cream.
D
The variability between each type of cream would be evenly distributed between the two groups, so any observed differences in the level of irritation between the two groups are guaranteed to be due to the subjects.