Which of the following is considered a reservoir for microorganisms?

• A. Other people; Animals; Soil; Food/Water/Milk; Inanimate objects
• B. Air only
• C. Water only
• D. Soil only

Answer: (A)

Microorganisms need somewhere to persist and potentially multiply, so a reservoir is any place where they live and remain capable of transmission. This includes other people, animals, soil, food, water (including milk and drinking water), and even inanimate objects that can carry microbes (fomites). That broad view is why the most complete answer is correct: it lists all these possible reservoirs. The other options narrow the concept to just air, or just water, or just soil, which doesn't capture the full range of places microbes can inhabit. Understanding reservoirs helps explain how infections spread and what to target to interrupt transmission.