Definition: 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: It is a larval stage in the biological cycle of trematodes: 
 Options:  <1> Procercoid <2> Plerocercoide. <3> Cercaria <4> Cisticerco <5> Cysticercoid
