Chemical bonds are likely to form when
an atom’s nucleus has the same number of protons as it does neutrons
two atoms have the same number of electrons
an atom’s outer energy level is filled to capacity
an atom’s outer energy level doesn’t have the maximum number of electrons

The answer to your question is the last option

Explanation:

an atom’s nucleus has the same number of protons as it does neutrons  to have the same number of protons and neutrons does not affect the ability of an atom to form bonds, so this option is wrong.

two atoms have the same number of electrons some atoms have that have the same number of electrons can form bonds, but most of the atoms that form bonds do not have the same number of electrons. This option is wrong.

an atom’s outer energy level is filled to capacity  this option is wrong because noble gases have the outermost energy level filled to capacity and are unreactive.

an atom’s outer energy level doesn’t have the maximum number of electrons an atom with the characteristics described are reactive, so this is the correct answer.

b.

the accuracy of the data.