[AUgrad2006]

If the foul comes before a change of possession, the scoring team doesn't have the option.

Example: A85 commits offensive pass interference but B26 still intercepts the ball and returns for a touchdown. Because the foul occurred before the interception, this does not qualify under any of the special circumstances in 8-2. Thus B would have to decline A's penalty in order to accept the results of the play.

That's just the first situation that comes to mind. There are probably others.

The thing to remember is that there are 3 situations where the live-ball penalty on a TD can be enforced on the ensuing kick:
1) B fouls on a play where there is no change of possession (8-2-2)
2) The non-scoring team fouls on a play where there is a change of possession AND the foul occurs after the change of possession (8-2-3)
3) EITHER team commits an unsportsmanlike or nonplayer foul during the play (8-2-4)

Additionally, any dead-ball foul which occurs after the score and up to the ready-for-play has the same penalty option for the offended team. (8-2-5)

And, as always, a foul by B on a successful try gives A the option to take the penalty on the kick. (8-3-5)