<span>Dalton's famous experiments using cathode ray tubes demonstrate the presence of electrons, of which Dalton was previously unaware. In his theories, Dalton posited that atoms were solid, indivisible particles. However, Thomson's experiments showed that there were in fact subatomic particles, ushering in a new era of study of the atom.</span>
The correct option is C. J.J Thompson demonstrated that Dalton's model of the atomic theory was wrong by showing that atoms are made up of sub particles, this is contrary to the report that Dalton gave about atoms. In his experiment, Dalton reported that atoms are indivisible, that is, they can not be broken down into smaller particles. J.J Thompson on the other was able to show through his cathode ray experiment that atoms are made up of smaller particles called electrons.
Basically the star slowly burns its hydrogen into Helium. Depending on the mass, the star will have a turbulent core where the Helium will be fully mixed or a radiative core where the helium will settle at the centre (remember it's heavier than Hydrogen). The second case is what happens in the Sun.