Which of the following hypothetical research findings would present a problem for researchers trying to interpret results from a twin-study design?
A. Parents of monozygotic twins treat the two twins more alike than do parents of dizygotic twins.
B. Dizygotic twins don't look as much like one another as do monozygotic twins.
C. Parents treat female pairs of twins differently than they treat male twins.
D. There are more dizygotic twins born each year than monozygotic twins.
Question 2
Research on genetic determinants of personality tell us that
A. personality is fixed at birth.
B. most, but not all, of adult personality is determined by genetics.
C. a significant percentage of adult personality is determined by genetics, but experience also plays a large role.
D. except for a few traits, there is very little genetic influence on personality.
