What is the process of pesticide degradation that does not involve living organisms?

Chemical degradation refers to the breakdown of pesticides through non-biological chemical reactions. This process can occur due to a variety of factors such as exposure to water, heat, or oxidizing agents. During chemical degradation, the molecular structure of the pesticide changes, leading to a loss of its effectiveness and ultimately rendering it harmless over time.

Photodegradation is another process that involves the breakdown of substances due to exposure to light, specifically ultraviolet light, which leads to chemical changes in the pesticide molecules. However, despite being a chemical process, it specifically relies on light as the degrading factor.

Microbial action, on the other hand, involves the action of microorganisms such as bacteria and fungi in degrading pesticides, making it a biological process rather than a purely chemical one. Inert degradation does not specifically describe a recognized process of pesticide breakdown.

Thus, the correctness of the answer lies in the fact that chemical degradation is the only process listed that clearly represents the degradation of pesticides without the involvement of living organisms, fulfilling the requirements of the question.