Research on the personality trait of extraversion has shown that its heritability is approximately 50 percent. What does this mean?
a. 50 percent of the population is extraverted.
b. For any given person, extraversion is determined half by genetics and half by environment.
c. Genetics can explain 50 percent of the differences in extraversion among the population at large.
d. For 50 percent of the population, extraversion is determined by genetics, while for the other 50 percent it is determined by environment.