What is the intake of food, medicine, and drink through the mouth into the body known as?

Ingestion is the term for the process of taking in food, medicine, and drink through the mouth into the body.

It is the first step in the digestive process and involves the intake of food, which is broken down by chewing and mixed with saliva in the mouth. The food is then formed into a bolus and swallowed, passing through the pharynx, oesophagus, and stomach.

Hence, the correct option is ingestion.