A Nonexcludable Good Is a Good in Which

A nonexcludable good is a good in which:

A) it is difficult to prevent someone from using or having access to the good.
B) one person consuming or using the good cannot prevent others from using or consuming the same unit of the good.
C) there is a regulation that the good must be provided to everyone.
D) the good has no cost of production and so is available to consumers at no cost.