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 to about:
Answer & explanation
Correct answer: option 1
The correct answer is Option (1) → 0.72
Twin studies show the role of heredity in intelligence. The correlations fall as the genetic link weakens or the environments differ:
identical twins reared together: almost 0.90
identical twins reared in different environments: 0.72
fraternal twins reared together: almost 0.60
brothers and sisters reared together: about 0.50
siblings reared apart: about 0.25
The other options are the figures for fraternal twins (0.60), siblings reared together (0.50) and siblings reared apart (0.25).
Note: A similar question was also asked in CUET (UG) 2023 on 02-07-2023 (Slot 3), and in CUET (UG) 2025 on 21-05-2025 (Slot 1).
NCERT (2025-26): “Intelligence: Interplay of Nature and Nurture … 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.…” |