With Regards to the Public Goods Game with Punishments, Whether

With regards to the public goods game with punishments, whether efficiency is higher or not depends on whether or not:

A) earnings are higher after subtracting the costs incurred in punishing others or the costs incurred in being punished.
B) contributions to the public account are higher regardless of any punishment costs.
C) people understand that free-riding is the dominant strategy.
D) earnings are higher before subtracting the costs incurred in punishing others or the costs incurred in being punished.