A
a nuclear beta decay

B
a nuclear alpha decay

C
a physical phase change

D
a chemical decomposition

Option B is correct. A nuclear alpha decay

Explanation:

Step 1

This equation is a nuclear reaction. So it can be an alpha decay or a beta decay

An α-particle is a helium nucleus. It contains 2 protons and 2 neutrons, for a mass number of 4.

During α-decay, an atomic nucleus emits an alpha particle. It transforms (or decays) into an atom with an atomic number 2 less and a mass number 4 less.

Thus, radium-226 decays through α-particle emission to form radon-222 according to the equation that is showed.

A Beta decay occurs when, in a nucleus with too many protons or too many neutrons, one of the protons or neutrons is transformed into the other.

Option B is correct. A nuclear alpha decay

answer

fusion: the energy source of stars. the energy released from the collapse of the gas into a protostar causes the center of the protostar to become extremely hot. when the core is hot enough, nuclear fusion commences. fusion is the process where two hydrogen atoms combine to form a helium atom, releasing energy.

hope it

i think   the answer is c hope i'm right