Instructions: 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'.
Input: Question: The ethanol-water mixture has an azeotrope, this means that:
Options: <1> From a certain concentration, the two liquids are immiscible. <2> The mixture has a minimum co-solution temperature. <3> Both components comply with Raoult's law. <4> The mixture is frozen at a single temperature. <5> Once the azeotropic composition is reached, the two liquids can not be separated by distillation.
Output:
5