3. Which one of the following modifications would have
enabled Delia to learn most
about the effectiveness of the two products in relieving insect bite pain?
A
Repeat the original applications.
B
Apply the different products randomly to different parts of her body.
C
After the original applications, apply the same products to the opposite sides of the
body.
D
As well as treating some bites with Esi-oil and some with Pine-elix, leave some of the
bites untreated.