Is oxygen necessary for the combustion of fuel?

Oxygen is indeed necessary for the combustion of fuel, making the statement true. Combustion is a chemical reaction that occurs when a fuel reacts with oxygen, producing heat and light. In this process, fuels—such as natural gas, gasoline, or wood—combine with oxygen from the air to release energy. This fundamental requirement is the basis for understanding how different boilers and combustion systems operate.

Without oxygen, combustion cannot occur; thus, all combustion processes require an oxidizing agent, typically atmospheric oxygen. This principle is why ensuring adequate air supply for any combustion process is crucial in boiler operation and design.

The other options introduce conditions or scenarios that do not align with the basic principles of combustion chemistry. While some fuels may burn more efficiently or differently under various conditions, it remains a fundamental fact that oxygen is essential for combustion itself.