Which of the following statement(s) is/are true about carbon monoxide?

Options

A. It is a colourless gas
B. It is an odourless gas
C. It is highly poisonous gas
D. All of the above

Answer

To determine which statements about carbon monoxide (CO) are true, we will analyze each statement provided in the question.

### Step-by-Step Solution:

1. **Understanding Carbon Monoxide**:
- Carbon monoxide is a chemical compound composed of one carbon atom and one oxygen atom. It is commonly produced from the incomplete combustion of carbon-containing fuels.

2. **Analyzing the Statements**:
- **Statement 1**: "It is a colorless gas."
- **Evaluation**: This statement is true. Carbon monoxide is indeed colorless, meaning it cannot be seen by the naked eye.

- **Statement 2**: "It is an odorless gas."
- **Evaluation**: This statement is also true. Carbon monoxide does not have a smell, which makes it particularly dangerous as it can go undetected.

- **Statement 3**: "It is a highly poisonous gas."
- **Evaluation**: This statement is true as well. Carbon monoxide is highly poisonous because it binds with hemoglobin in the blood more effectively than oxygen, reducing the blood's ability to carry oxygen to vital organs and tissues.

3. **Conclusion**:
- Since all three statements about carbon monoxide are true, the correct answer is that all of the statements provided are true.

### Final Answer:
All of the statements about carbon monoxide are true.