Monozygotic twins raised together have a higher correlation in IQ scores than MZ twins raised apart. This offers proof that
A) intelligence is determined by one's genetic makeup.
B) adoption affects IQ scores more than biology does.
C) there may be an environmental influence on intelligence.
D) MZ twins raised together learn from each other.

Question

Quizplus · Accepted Answer

The fact that MZ twins raised together have a higher correlation in IQ scores than MZ twins raised apart suggests that there may be an environmental influence on intelligence. If intelligence were solely determined by genetics, then MZ twins raised apart would have similar IQ scores as MZ twins raised together. The fact that this is not the case suggests an environmental influence on intelligence. Adoption may still play a role in IQ scores, but this specific data suggests that genetics alone are not the sole determinant of intelligence. The answer D is not a strong inference that can be drawn from this data, as it is possible that MZ twins raised apart can still learn from each other through other means (e.g. communication, visits).

Monozygotic Twins Raised Together Have a Higher Correlation in IQ