Consider the following passage from The Adventures of Tom Sawyer: "There are wealthy gentlemen in England who drive four-horse passenger coaches twenty or thirty miles on a daily line, in the summer, because the privilege costs them considerable money; but if they were offered wages for the service that would turn it into work then they would resign." This passage illustrates the concept of ____

Which of the following is a valid statement relating to research concerning genetic influence on cognitive abilities?

a. Fraternal twins have higher correlations on scores of cognitive functioning than do monozygotic twins. b. Different types of cognitive abilities are influenced to the same extent by genetics. c. For general cognitive ability, heritability decreases with age. d. Meta-analyses of variance in IQ scores among twins suggest that 50% of the variance can be explained by genetic differences.

Research suggests that adolescents who are adopted by a family with a different ethnic background than their own have lower self-esteem and take longer to adjust to their new family

Indicate whether the statement is true or false