10 free CLEP Psychology practice questions in the real exam format, covering the official content areas, with an explanation for every answer.
CLEP Psychology Practice Test 13Tutor mode
Question 1 of 10
Biological Bases of Behavior
Researchers studying a personality trait find that identical twins raised in different homes are about as similar as identical twins raised together, and both groups are much more similar than fraternal twins raised together. This pattern most strongly suggests that: