Mary age 10 has asthma and her parents bought a high air frequency filter for bedroom This represents which level of prevention Primary secondary or tertiary?

Primary prevention.

Primary prevention is aimed at preventing the occurrence of disease or injury before it has a chance to develop. In this case, the high air frequency filter is being used to improve air quality and reduce the risk of asthma attacks. This is an example of primary prevention because it is aimed at preventing the development of asthma in the first place.