A stable Helium-4 nucleus has two protons and two neutrons. If the mass of Helium-4 nucleus, proton and neutron are denoted by mHe, mp and mn respectively, we can conclude that:
a) mHe=2mp+2mn.
b) mHe>2mp+2mn.
c) mHe<2mp+2mn.
d) Any of the above may be true.