Ecology simply means the study of

Step 1: Analyze the question The question asks for the simple definition of ecology.

Step 2: Explain the concept The word comes from the Greek oikos (house or home) and logos (study). So ecology is the study of "homes", meaning how living things relate to the place where they live. It covers:

• Relationships among organisms (feeding, competition, symbiosis)
• Relationships between organisms and the abiotic (non-living) environment, such as soil, water, temperature and light

Step 3: Check each option

• A. Particular species of plants and animals: This describes taxonomy or the study of specific species, not ecology.
• B. The interrelationship between organisms and their environment: This is the standard definition. It covers living things and their surroundings (biotic and abiotic).
• C. The properties of a habitat: This is too narrow. It describes the habitat only and leaves out the organisms and how they interact with it.
• D. The interrelationship between plants and animals: This leaves out other organisms such as fungi and bacteria. It also ignores the physical environment.

Step 4: Answer

Exam tip: Remember ecology as "organisms + environment + interaction". If an option contains all three ideas, it is almost always the right one. Also watch for options that mention only plants and animals, or only the habitat. They are usually traps.