Answer:
d. it can be greater than the atomic number
Explanation:
Atomic mass number can be defined as the sum of number of protons and number of neutrons present in the nucleus of an atom. On the other hand, atomic number is determined by the number of protons present in the nucleus of the atom. Thus, atomic mass number can be equal or greater than the atomic number but cannot be less than it. Hydrogen has 1 proton and 0 neutrons. So, atomic mass number and atomic number are equal. For rest, the atomic mass number is greater than the atomic number. Thus, option d is correct.
