The lowest temperature at which a substance catches fire and starts burning is called

Options

A. rusting
B. ignition temperature
C. calorific value
D. all of these.

Explanation

To answer the question about the lowest temperature at which a substance catches fire and starts burning, we can follow these steps:

### Step-by-Step Solution:

1. **Understanding the Concept**:
- The question asks for the term that describes the lowest temperature at which a substance can ignite and start burning.

2. **Identifying Key Terms**:
- The term "ignition" is crucial here. It relates to the process of starting a fire.

3. **Defining Ignition Temperature**:
- The ignition temperature is defined as the minimum temperature required for a combustible substance to catch fire.

4. **Explaining the Importance**:
- If the temperature of the substance does not reach this ignition temperature, it will not ignite or burn.

5. **Conclusion**:
- Therefore, the answer to the question is that the lowest temperature at which a substance catches fire and starts burning is called the **ignition temperature**.

### Final Answer:
The lowest temperature at which a substance catches fire and starts burning is called the **ignition temperature**.

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