Question

which of the following is true about nuclear fission? nuclear fission has been observed, but not on earth. nuclear fission is what makes nuclear weapons work. nuclear fission has never happened before.

Explanation:

Nuclear fission is the process of splitting atomic nuclei, which releases a large amount of energy. Nuclear weapons, such as atomic bombs, operate based on nuclear fission. Nuclear fission has been observed on Earth in nuclear reactors and nuclear weapons. It is not a phenomenon that has never occurred before.

Answer:

Nuclear fission is what makes nuclear weapons work.