Which of the following is a colourless, odourless, neutral gas which supports combustion but is not combustible?

The gas that is colourless, odourless, neutral, supports combustion but is not combustible is oxygen (O₂).

Explanation:

• Oxygen supports combustion because it is a strong oxidizing agent that reacts with fuels during the process of burning.
• However, it is not combustible itself, meaning it does not burn independently but facilitates the combustion of other substances.