What describes the injection or application of a substance to the human body?

The correct answer is the term "administration." This term specifically refers to the process of delivering or applying a substance, such as a medication or drug, to the human body. In medical and pharmacological contexts, administration encompasses various routes through which substances can enter the body, including intravenous, intramuscular, subcutaneous injections, oral intake, and more. This term is widely used to indicate how a treatment is given to a patient.

In contrast, the other options do not capture the process of delivering a substance accurately. "Human consumption" generally refers to the intake of food or drink, rather than the method of introduction of substances, while "overdose" pertains to an excessive intake of a substance beyond safe or therapeutic levels. "Absorption" describes the process by which the body takes in a substance after it has been administered, rather than the act of delivery itself. Therefore, "administration" is the most precise term to describe the injection or application of a substance to the human body.