Which of these statements about natural gas is true?

Options

A. It generates a lot of pollution.
B. It smells like rotten eggs.
C. It is mildly flammable.
D. It is colorless.

Answer

To determine which statement about natural gas is true, let's analyze the given options step by step:

1. **Statement Analysis**: We need to evaluate each statement about natural gas to find the one that is true.

2. **Statement 1**: "Natural gas generates a lot of pollution."
- **Evaluation**: This statement is false. Natural gas is known to produce less pollution compared to other fossil fuels like coal and oil. It burns cleaner, emitting fewer pollutants.

3. **Statement 2**: "Natural gas smells like rotten eggs."
- **Evaluation**: This statement is also false. Natural gas itself is odorless. However, an odorant (usually mercaptan, which smells like rotten eggs) is added for safety reasons to help detect leaks.

4. **Statement 3**: "Natural gas is mildly flammable."
- **Evaluation**: This statement is incorrect. Natural gas is highly flammable, meaning it can catch fire easily and burn rapidly.

5. **Statement 4**: "Natural gas is colorless."
- **Evaluation**: This statement is true. Natural gas is indeed colorless and odorless in its natural state.

6. **Conclusion**: After evaluating all the statements, the true statement about natural gas is that it is colorless.

### Final Answer:
The true statement about natural gas is: "Natural gas is colorless."

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