What is an aerosol?

An aerosol refers to a system in which tiny solid or liquid particles are dispersed throughout a gas. The key characteristic of an aerosol is that it consists of a mixture of these particles suspended in a gaseous environment. This phenomenon is typically found in various contexts such as sprays, mists, and fogs, where the particles, which can be liquid droplets or solid particles, are suspended in air or another gas.

In this case, the correct answer emphasizes the gaseous suspension aspect of aerosols, highlighting their nature as a mix of particles under pressure. This is relevant since many aerosol products, such as spray paints or deodorants, utilize pressurized containers to disperse the active ingredients in a fine mist, making them easy to apply and ensuring an even distribution.

The other options do not accurately describe aerosols. A solid particle suspended in liquid does not account for the gas component, a liquid with a high flash point describes a specific property of liquids, and solid waste material does not relate to the concept of a dispersed phase in gases. Thus, the focus on the gaseous aspect and particle suspension makes the correct choice clear.