C. The temperature decreases because the most energetic molecules escape.
I'm not so sure but I would say Answer Choice B
The question is incomplete but i will try to offer as much help as i can.
Answer:
See explanation
Explanation:
The electron was discovered by J.J Thompson. His model of the atom was called the plum-pudding model of the atom.
He discovered that cathode rays being negatively charged particles were deflected by a magnet in just the same way as moving, negative electrically charged particles.
Similarly, in an electric field, they are deflected towards the positive plate of the electrostatic field which shows that they are negatively charged.
