Question Detail
Question
The sex-determination system in which males are XY and females XX is found in all
Correct Answer
Option D is the correct answer.
Detailed Explanation
The XX/XY sex-determination system is characteristic of all mammals. While many other animals and some plants use this system, it is not universal. For example, birds have a ZW system (males are ZZ, females are ZW), and many reptiles use temperature-dependent sex determination.
Hint
This system is a defining feature of the group of animals that have hair and produce milk.