Given the task definition and input, reply with output. In this task, you are given a multiple-choice question about healthcare. Answer the question based on your information and classify your answers into '1', '2', '3', and '4'.

Question: Orally administered proton pump inhibitor drugs:
Options: <1> Neutralize hydrochloric acid from gastric secretion. <2> They dye the stools black. <3> They block the histaminergic receptor. <4> They block the gastrin receptor. <5> They require enteric cover.
5