Which contaminants can be effectively trapped in a filtration bed?

Filtration beds are commonly used in water treatment processes to remove various contaminants, making them an essential component in ensuring safe drinking water and protecting the environment. When considering which contaminants can be effectively trapped in a filtration bed, it's important to understand its capabilities and the types of materials used within the bed.

Microorganisms, such as bacteria, viruses, and protozoa, can be physically removed from water as they are larger than the pore spaces in the filtration media. The process of mechanical filtration allows these pathogens to be captured, thus reducing the risk of waterborne diseases.

Heavy metals, such as lead, mercury, and arsenic, can also be effectively trapped in filtration systems, especially when activated carbon or specific media are employed. These materials have the chemical affinity to adsorb heavy metals, thereby lowering their concentrations in the water.

In contrast, other options focusing exclusively on pesticides or organic compounds do not encompass the full range of contaminants that filtration beds can address. Pesticides and organic compounds may require specialized treatment processes or different types of filters, which do not typically fall under the standard filtration bed category designed for broad-spectrum removal of contaminants.

Consequently, the correct answer highlights the comprehensive capability of filtration beds to trap both microorganisms and heavy metals, making