What are the primary combustible elements in waste management?

The primary combustible elements in waste management are carbon, hydrogen, and sulfur. Carbon and hydrogen are fundamental constituents of organic materials, which are prevalent in various types of waste, such as food waste, paper, and plastics. When these substances are incinerated, they combust readily, producing heat and contributing to the energy recovery from waste.

Sulfur, while present in smaller quantities, is also significant as it can be found in certain organic waste and materials like rubber and some plastics. Its presence is important to consider, particularly regarding the emissions generated during combustion processes.

The other options listed do not have the same relevance in terms of combustible elements. Oxygen is necessary for combustion but is not a fuel; it's an oxidizer. Nitrogen and argon are inert and do not contribute to combustion directly. Helium, being a noble gas, also does not participate in combustion processes, making it irrelevant in this context. Thus, the choice highlighting carbon, hydrogen, and sulfur accurately identifies the key combustible elements significant to waste management practices.