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 Baltimore system of virus classification is based on:
Options: <1> The type of genetic material (DNA or RNA) they possess. <2> The morphology of their virions. <3> The replication of the genome and the synthesis process of its mRNA. <4> The symmetry of the capsid. <5> The presence or absence of wrapping.
Output:
3