The number of protons plus the number of neutrons equals A. the atomic mass. B. the number of bonds the atom can form. C. the electrical charge of the atom. D. the atomic number. E. the number of electrons.

Answer : The correct option is, (A) the atomic mass

Explanation :

Atomic number : It is defined as the number of protons or number of electrons.

Atomic number = number of protons = number of electrons

Mass number : It is defined as the sum of number of protons and number of neutrons.

Number of neutrons = Mass number - Number of protons

or,

Mass number or atomic mass = Number of protons + Number of neutrons

For example :

Atomic number of carbon = 6

Number of proton = Atomic number = 6

Number of neutrons = 6

Mass number = 6 + 6 = 12

Hence, the correct option is, (A) the atomic mass.