What type of organization will this essay use?

Types of Friends

I. Acquaintances
A. People you hardly know but say “Hi” to anyway
II. Family friends
A. Your family
B. Friends of your family
III. Good friends
A. People you see on a regular basis, at least once a week
IV. Best friends
A. People you talk to or see everyday

chronological order

simple list

order of importance

order of importance