Therm is the unit of

Options

A. heat
B. temperature
C. thermometry
D. work

Explanation

**Step-by-Step Solution:**

1. **Identify the Unit**: The question asks about the unit "therm." We denote it as "THM."

2. **Define Therm**: The therm is a non-SI unit that measures heat energy. It is important to recognize that it is not part of the International System of Units (SI).

3. **Origin of the Unit**: The therm was defined in the United States and is used primarily in the context of natural gas.

4. **Energy Equivalent**: One therm is defined as the energy equivalent of burning 100 cubic feet of natural gas at standard temperature and pressure (STP).

5. **Conclusion**: Based on the definition and context, we conclude that the therm is a unit of heat energy.

6. **Options Analysis**: If presented with multiple-choice options, we would confirm that the only correct answer is that therm is a unit of heat energy, ruling out other options like temperature or work.

**Final Answer**: Therm is the unit of heat energy.

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