Answer:
b. Differences in intelligence between identical twins must be due to differences in their environments.
Step-by-step explanation:
Almost all psychologists agree that heredity and environment are important in determining each individual's level of intelligence. Disagreements arise as to the relative weight of each of the factors. However, psychologists today tend to be more interested in how the two factors interact than in which one matters most.
According to this concept, it was established that in identical twins, heredity would influence the same level of intelligence, but different environments would influence different intelligences, that is, differences in intelligence between identical twins must be due to differences in their environments.