Final answer:
Age constitutes a subculture primarily due to common experiences and perspectives among individuals, especially the elderly, who form communities with shared values and interests related to aging.
Step-by-step explanation:
Age constitutes a subculture primarily because of B) Common experiences and perspectives. This stems from the concept of the subculture of aging theory, wherein individuals, particularly the elderly, tend to form their own communities. These communities are characterized by shared values, beliefs, and interests that arise from their shared experiences of aging. They can develop group consciousness around issues like the Medicare "doughnut hole," creating social and political pressure to address these issues. While individuals in an age-based subculture may be brought together by diverse factors such as social or political interests, they are predominantly unified by their common experiences and perspectives on aging.