**Question:** Study unit of ecological study is

A. Individual
B. Population
C. Community
D. Ecosystem

**Core Concept:** In ecology, an ecological study involves examining the interactions between organisms and their environment. The main study units are at different levels of organization: individuals, populations, communities, and ecosystems.

**Why the Correct Answer is Right:** The correct answer, **B. Population**, refers to a group of interbreeding individuals of the same species living in the same area. It is the appropriate unit for studying population dynamics, such as birth, death, and migration rates.

**Why Each Wrong Option is Incorrect:**

A. **Individuals (A)** are the smallest unit of study in ecology, but studying individuals alone does not capture the larger ecological processes and interactions.

C. **Communities (C)** are groups of interacting populations, but they do not represent a standard study unit, as studying communities ignores the individual and population levels.

D. **Ecosystems (D)** are larger units comprising a community, climate, and abiotic factors. While ecosystems are important in ecology, they are not the primary study unit for examining ecological relationships.

**Clinical Pearl / High-Yield Fact:** In ecology, understanding population dynamics is essential for conservation and management strategies, as it helps predict the effects of environmental changes or human interventions on species numbers and biodiversity.

**Correct Answer:** B. Population