To study __________ possibility, the scientist uses two groups of people who are over 75 years of age and have mild memory loss.
The control group receives 100 pills that contain fish oil. The ________ group receives similar pills that don’t contain any active ingredients. These fake pills are called placebos.
"To study this possibility, the scientist uses two groups of people who are over 75 years of age and have mild memory loss. The control group receives 100 pills that contain fish oil. The control group receives similar pills that don’t contain any active ingredients. These fake pills are called placebos."
