Q: 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 delirious atmosphere is defined as:
Options: <1> The delirious interpretation of a normal perception. <2> A self-referential idea, of great importance for the patient. <3> Subjective experience that the world has changed in a subtle but sinister, disturbing and difficult or impossible to define way. <4> The delirious construction of a memory. <5> A rational and easily modifiable idea about an environmental issue.
A:
3