With respect to both InGold and Force's comments regarding b) and my comment about something from nothing.
To InGold, I suggest you read Lawrence Krause's "A Universe From Nothing" which was just released last month. It is a very easily accessible summary of the current understanding of science in this matter.
To Force, virtual particles are one form of particles that pop into existence from nothing. Dirac's example is of positron-electron pairs that pop into existence but have a combined energy = 0. While they usually only appear for periods which are not directly observable, they can be indirectly observed and it has been established that the particles can be separated and thereby exist for longer than insubstantial periods. This is not new scientific principles, though the "proofs" of it are relatively recent. The point is that these particles are not particles that we do not know exist. This isn't stuff like the Higgs Boson which are still hypothetical.
Point being is that the scientific consensus is that something can come from nothing and that it regularly does.