Investigators interested in the effects of nutrition on wound healing randomly assigned patients recovering from burn injuries to two groups. One group received protein supplements and the second group did not. The random assignment was used to:
A. eliminate the systematic influence of any other variable.
B. provide a control for earlier nutritional status.
C. make the groups equal in terms of the dependent variable.
D. obtain groups equal in number.
Question 2
There are several ways in which confounding extraneous variables can be controlled. Which control technique is considered the best?
A. matching
B. random assignment
C. counterbalancing
D. selection
Wound healing
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