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: The great diversity of immunoglobulins is mainly due to the recombination of: 
 Options:  <1> Epitopes. <2> Light chains <3> Heavy chains <4> Exons <5> Introns
