You will be given a definition of a task first, then some input of the task.
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: The structures of the condensed chromosomes are maintained by: 
 Options:  <1> Topoisomerases <2> Nucleolus proteins. <3> Fragments of Okazaki. <4> SMC proteins. <5> DNMT1 protein.
Output:
4