Combustion is aA.chemical processB.physical processC.both of these processesD.none of these processes.

Combustion is a A. chemical process.

Here's why:

Combustion is a high-temperature exothermic redox chemical reaction between a fuel and an oxidant, usually atmospheric oxygen, that produces oxidized, often gaseous products, in a mixture termed as smoke. This process involves breaking and forming of chemical bonds, which is a characteristic of a chemical process.

Physical processes, on the other hand, involve changes in the state or properties of matter without any change in its molecular structure. An example of a physical process is the melting of ice into water; no new substance is formed in the process.

Therefore, combustion is not a physical process, but a chemical one.