Spot out the odd one.

Options

A. Calorie
B. kilowatt hour
C. joule
D. watt

Explanation

To solve the question "Spot out the odd one," we need to analyze the given options:

1. **Calorie**
2. **Kilowatt per hour**
3. **Joule**
4. **Watt**

### Step 1: Identify the categories of each option

- **Calorie**: This is a unit of energy. It measures the amount of energy needed to raise the temperature of 1 gram of water by 1 degree Celsius.

- **Kilowatt per hour**: This is also a unit of energy. It measures the amount of energy consumed when a power of 1 kilowatt is used for 1 hour.

- **Joule**: This is another unit of energy. It is defined as the energy transferred when a force of one newton is applied over a distance of one meter.

- **Watt**: This is a unit of power. It measures the rate of energy transfer equivalent to one joule per second.

### Step 2: Group the options based on their categories

From the analysis:
- Calorie, Kilowatt per hour, and Joule are all units of energy.
- Watt is a unit of power.

### Step 3: Identify the odd one out

Since calorie, kilowatt per hour, and joule are all units of energy, and watt is a unit of power, we can conclude that:

- The odd one out is **Watt**.

### Conclusion

Thus, the answer to the question is **Watt**.

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