Which of the following identifies the routes by which a poison can enter the human body?

The correct identification of the routes by which a poison can enter the human body is best represented by ingestion, inhalation, injection, and absorption. Each of these routes highlights a specific method through which toxins can affect an individual.

Ingestion refers to the intake of poison through the mouth, where it can enter the gastrointestinal tract. Inhalation involves breathing in toxic substances, which can rapidly enter the bloodstream via the lungs. Injection indicates the direct introduction of poison into the body through the skin or other tissues, often via needles. Absorption pertains to the process where a toxin passes through the skin or mucous membranes and into the bloodstream.

This comprehensive view captures the common pathways for poison entry and helps in understanding how different scenarios of exposure can lead to toxic effects, making it imperative for responders to recognize these routes for effective assessment and intervention in toxicologic emergencies.