Which of the following is an assumption of stage theories of development? A. A person’s age is good indicator of what period of development one is in. B. A person’s experience is a good indicator of what period of development one is in. C. A person’s learning is a good indicator of what period of development one is in. D. A person’s history of social encounters is a good indicator of what period of development one is in. Please select the best answer from the choices provided A B C D.