Sexual dimorphism a. refers to differences between the sexes with regard to features such as body size b. refers to differences between adults and adolescents with regard to sexual behavior c. is particularly pronounced in all primate species d. is more common in arboreal species e. has not been observed in any monkey

The correct option is a. refers to differences between the sexes with regard to features such as body size

Explanation:

Sexual dimorphism refers to a specific condition in animals and plants, which includes difference in the secondary characteristics of the male and female sexes of the same species. Sexual dimorphism is seen in many animals and some plant species. The difference in the secondary characteristics includes size, color, behavior, etc.