Which of the following processes helps reduce the concentration of a chemical substance in the body?

Detoxification is the process through which the body metabolizes and eliminates toxic substances, including chemical substances that may have entered the body. This process is crucial for maintaining homeostasis and overall health. It typically occurs primarily in the liver, where enzymes convert harmful substances into less harmful compounds, which can then be excreted through urine, feces, or bile.

By enhancing the elimination of these substances, detoxification effectively reduces their concentration within the body's systems, thus preventing potential damage to cells and organs. This protective mechanism allows the body to maintain its internal environment, safeguarding it against the harmful effects of accumulated toxins.

While absorption refers to the uptake of substances into the body, concentration pertains to the buildup of substances rather than their reduction. Aggregation typically involves clustering or grouping of substances, which does not relate to reducing their concentration. Therefore, the correct answer illustrates a key biological function that actively works to cleanse and maintain the body's integrity against harmful agents.