pronouns - Under which conditions can "one" be used to refer to non human entity?

I've heard that one is understood as referring to people if one uses any one as in

Q: Which of these ice cream flavors do you want?
A: Any one.

I understand that any one sounds like anyone, but is that a reason not to use the expression?

What about other uses of one, such as the first one and one of them?

Answer

"One" is used as a pronoun for things and people.

Things:

• "Please hand me the one on the right."


• "John wants the same one as all his friends."


• "Having only one is never enough."

People:

• "Mary is the one who gave me this cold."


• "The one on the right is my sister."


• "Go in one at a time, please."