Which term describes individuals who are similar in age and stage of development?

The term that describes individuals who are similar in age and stage of development is "peers." Peers typically refer to individuals who share similar experiences, interests, and social status due to their proximity in age. This peer group is important in socialization, as they often influence behavior, attitudes, and social skills during various developmental stages, particularly in adolescence.

In contrast, family members are individuals related by blood or marriage, and while they may include some similar-aged individuals, they can also encompass varying ages and stages of life. Adults refer more broadly to fully developed individuals, but they do not specifically denote similarity in age and stage of development. Mentors, on the other hand, are typically individuals with more experience who guide or support others, and they often play a different role than peers in one's life. Thus, among the given choices, "peers" is the most accurate term for individuals in similar age and development stages.