Answer:
c. hallucinations
Step-by-step explanation:
Hallucinations: In abnormal psychology, the term hallucination refers to the process of experiencing sensations by a person that may appear as to be real or true but it has been created in the mind of the person.
Example: Hearing voices, seeing things that aren't physically present.
Hallucination includes hearing, feeling, seeing, tasting, or smelling something that is not physically present.
In the question above, Nick's symptoms are known as hallucinations.