Ever notice that, at the beginning of the game, each team brings out four players for the coin toss? Those are the team’s captains for that game; one of them is “the” captain at any given time, and that is the person asked by officials whether or not to accept a penalty.
This is what I was going to say. The Captains probably do the talking, but during the game, you’ll see them look to the sidelines for guidance in this situation (often making the decline symbol to confirm thats what the coach wants, for example)
I get the feeling that when the choice is obvious the officials just make the call. When watching games when such situations arise, the refs seem to immediately make the call.
To add on to this question, I know they can change their mind on accepting a penalty if a challenge/review reverses the play. Is there any other time they can change their mind? More than once I’ve seen a third down penalty declined, only to have the offense end up kicking a field goal or converting on 4th down.
You sometimes see the official exchanging signs with the head coach before they make the accepted/decline announcement in situations where it is a judgment call.
In practice the head referee will look towards the sideline & the coach to confirm the accept/decline decision when it isn’t a “no-brainer” type of penalty to take.