The strongest support for heredity’s influence on intelligence is the finding that a. identical twins, but not other siblings, have nearly identical intelligence test scores. b. the correlation...

The strongest support for heredity’s influence on intelligence
is the finding that
a. identical twins, but not other siblings, have nearly
identical intelligence test scores.
b. the correlation between intelligence test scores of
fraternal twins is not higher than that for other siblings.
c. mental similarities between adopted siblings increase with
age.
d. children in impoverished families have similar intelligence
scores.