Group of individuals of one species

• A. Ecosystem
• B. Population
• C. Community
• D. Organ System

Answer: (B)

A population is a group of individuals of the same species living in a defined area and capable of interbreeding, sharing a gene pool. This distinguishes it from other levels: an ecosystem includes all living organisms plus the physical environment; a community is all the populations of different species in that area; and an organ system is a set of organs within a single organism. For example, a herd of deer in a forest is a population, the forest with all plants and animals is an ecosystem, all populations in the forest form the community, and the circulatory system is an organ system inside a deer. So, the group described as “Group of individuals of one species” is a population.