Since Nuclear Fusion in the Sun Creates Energy from Matter

Since nuclear fusion in the Sun creates energy from matter, why doesn't it violate the law of conservation of energy?

A) Conservation of energy only applies to mechanical and electrical systems, not to nuclear physics.
B) The energy actually comes from the motion of the four separate hydrogen atoms, which move less bound together as one helium atom.
C) Matter and energy are equivalent, as expressed by Einstein's equation E = mc ².
D) It does, but conservation of energy is only a law in Newtonian physics, which does not work under the conditions at the center of the Sun.