Analogy — “Intestine : Liver : Heart”. Pick the option that belongs to the same internal-organ category.

Introduction / Context:
The trio lists internal organs. Select the option that is also an internal organ.

Given Data / Assumptions:

• We aim for organ-level classification, not tissue or external body part.

Concept / Approach:
“Kidney” is an internal organ (urinary system). Blood is tissue/fluid; hand/forehead are external body parts; tooth is a hard tissue/structure.

Step-by-Step Solution:

Verification / Alternative check:
Human anatomy confirms kidney as an organ.

Why Other Options Are Wrong:
They are not organs in the same sense.

Common Pitfalls:
Confusing tissue/structures with organs.

Final Answer:
Kidney