What solid particles are generated during the combustion process?

Flyash is the correct response because it consists of the fine particles suspended in the flue gas produced during the combustion of fossil fuels, particularly coal. When coal is burned, various minerals and inorganic materials do not combust and instead are transformed into fine particles. These particles can be carried away with the exhaust gases and collected through pollution control devices.

While slag forms from the larger, melted portions of ash that may settle or accumulate at the bottom of a furnace, it is not considered a solid particle in the same sense as flyash during combustion. Charcoal refers to a byproduct of burning wood in a low-oxygen environment, which does not directly relate to the combustion process of fossil fuels or the particles produced in large-scale industrial applications. Coal dust is a fine particulate matter that is a byproduct of handling and processing coal, but it does not originate from the combustion process itself. Therefore, flyash is the most accurate choice for solid particles generated specifically during combustion.