It's writen in omniscient narration.
The narration is in first person because it uses pronouns such as 'I'. F Scott Fitzgerald uses Nick Carraway to narrate the story and makes him tell it as if he were there which makes it first person.
a person involved in the story.
It is still called 1st person narration
In first-person narration the narrator is usually a participant in the story's action.
first-person narration
Answer is A: First Person
Common
A first person narrator is the person telling the story; they use words like "I" and "we."
First person narration is usually in first person point of view.
Ulrich Fries has written: 'Uwe Johnsons \\' -- subject(s): First person narrative, History, Narration (Rhetoric), Political and social views
A typically Modernist approach to narration and point of view is called first person literature. First person has the title character telling a story.
Jenny Mander has written: 'Circles of learning' -- subject(s): First person narrative, French fiction, History, History and criticism, Narration (Rhetoric)