What is the App Store Advertising Identifier (IDFA)?

Hi,

I´m uploading an app to itunesconnect and I´m using for the first time the Milkman Games Native extension for Admob and I´m being asked if my app uses the Advertising Identifier (IDFA). Can anyone tell me if it does and how I should answer these questions?

This app uses the Advertising Identifier to (select all that apply):

Attribute an action taken within this app to a previously served advertisment

Thanks