Analogy — “Length : Metre :: Power : ?”. Choose the SI unit that completes the mapping.

Introduction / Context:
Metre is the SI unit for length. We must select the SI unit for power.

Given Data / Assumptions:

• Use standard SI base/derived units.

Concept / Approach:
Power is measured in watt (W). Joule measures energy, kilogram measures mass, degree is temperature/angle, calories measure energy in another system.

Step-by-Step Solution:

Verification / Alternative check:
Physics convention confirms watt for power.

Why Other Options Are Wrong:
They are units of different quantities.

Common Pitfalls:
Confusing energy (joule/calorie) with power (rate of energy).

Final Answer:
Watt