A. Fraternal twins reared together.
B. Identical twins reared together.
C. Brothers, sisters reared together.
D. Siblings reared apart.
E. Identical twins reared in different environments.
Choose the correct answer from the options given below:
Answer & explanation
Correct answer: option 3
The correct answer is Option (3) → B, E, A, C, D
The closer the heredity and the shared environment, the higher the correlation between two people’s intelligence. From the highest correlation down:
(B) Identical twins reared together. — about 0.90: the same genes and the same home.
(E) Identical twins reared in different environments. — 0.72: the same genes, though brought up apart.
(A) Fraternal twins reared together. — about 0.60.
(C) Brothers, sisters reared together. — about 0.50.
(D) Siblings reared apart. — about 0.25, the lowest of the five.
NCERT (2025-26): “Intelligence: Interplay of Nature and Nurture … The evidence for hereditary influences on intelligence comes mainly from studies on twins and adopted children. The intelligence of identical twins reared together correlate almost 0.90. Twins separated early in childhood also show considerable similarity in their intellectual, personality and behavioural characteristics. The intelligence of identical twins reared in different environments correlate 0.72, those of fraternal twins reared together correlate almost 0.60, and those of brothers and sisters reared together correlate about 0.50, while siblings reared apart correlate about 0.25.…” |