Which of the following is not one of the four methods of allergen/poison exposure?

The method not recognized as one of the four primary ways allergens or poisons can enter the body is insertion. The four accepted routes typically include injection, ingestion, inhalation, and dermal absorption.

Injection refers to substances entering the body through a needle, as seen with bee stings or certain medications. Ingestion involves consuming the allergen or poison, for example, when a person eats a food that they are allergic to. Inhalation signifies the entry of allergens or toxins through the respiratory system, commonly observed with pollen or smoke exposure.

Insertion, while it suggests the idea of placing something into the body, isn't a standard classification in the context of allergen or poison exposure methods. Therefore, it is not included in the recognized avenues for how these substances affect the body.