What form does airborne contamination take in the environment?

Airborne contamination primarily consists of dust, vapours, or gases. This form of contamination occurs when harmful particles or substances are suspended in the air, making them capable of being inhaled or absorbed by living organisms. Dust can be a significant component of airborne contaminants, arising from various sources such as industrial activities, soil erosion, or construction work. Vapours refer to the gaseous state of a substance that can be released into the air, often from volatile organic compounds or chemicals, while gases include emissions from vehicles, factories, or natural processes.

The correct answer reflects an understanding of how contaminants can become airborne and the various forms they can take, emphasizing the health and environmental risks associated with inhalation or exposure to these substances. Other options, such as solid particles, liquid waste, or biohazard materials, do not capture the essence of airborne contamination as effectively, as they either represent a different state of matter or specific categories of waste that are not inherently airborne.