Final answer:
Sex determination in humans and other mammals is based on sex chromosomes, while other animals may use environmental factors or a combination of factors.
Step-by-step explanation:
The sex determination in humans and other mammals is indeed based on the presence of sex chromosomes. However, in other types of animals, there are different factors that determine sex. For example, in certain reptiles like alligators and some turtles, the sex is determined by the temperature during egg development. This is known as temperature-dependent sex determination, where cooler temperatures result in males and warmer temperatures result in females. So, the correct answer is option b) Yes, other animals may use environmental factors or a combination of factors.