Question

what characteristic does an organisms niche in an ecosystem define? reproductive age territory role

Explanation:

In ecology, an organism's niche refers to its role in the ecosystem, including how it interacts with other organisms and its environment (e.g., what it eats, how it obtains resources, its relationships with predators/prey). "Reproductive age" is about an organism's life stage for reproduction, and "territory" is a physical area an organism defends, not the core definition of a niche. So the correct option is the one related to the organism's role.

Answer:

role (the option with text "role")