Which statements correctly describe the process of nuclear fusion?

it happens only to large atoms.
it occurs naturally in the sun.
it releases a large amount of energy.
it bonds atoms together to create molecules.
it involves the joining of two atomic nuclei.

The following options are correct about nuclear fusion

In Physics ,a nuclear fusion is a reaction in which two or more atomic nuclei are combined to form one or more different atomic nuclei. It releases a large amount of energy and the nucleus made by fusion is heavier than either of the starting nuclei. This reaction naturally occurs on the sun as Hydrogen atoms are fused together to make helium.

explanation:

let the different atoms be x and y. each with four protons and same mass will be represented as follows.

mass number is number of protons + number of neutrons.

            and  

since, it is given that one has a negative charge while the other is neutral. therefore, there will be increase in number of protons and the atom will be represented as follows.

according to periodic table, mass number of beryllium is 9 and it has atomic number 4 so, the atoms will be and .  

the protons and neutrons will be located inside the nucleus whereas the electrons will be revolving around the nucleus.