Which statement best explains how isotopes can have different masses and still be the same element?

A.
The quantity of protons identifies the element but changes if the mass of the isotope differs from what is shown on the periodic table.

B.
The quantity of protons identifies the element and cannot change; therefore, the neutron amount changes, ultimately changing the overall mass of the atom.

C.
The sum of the electrons and neutrons equals the isotope's mass with the proton amount being given by the atomic number.

D.
The sum of the protons and electrons equals the mas

Question

Which statement best explains how isotopes can have different masses and still be the same element?	
 
 A.
The quantity of protons identifies the element but changes if the mass of the isotope differs from what is shown on the periodic table.
 
 B.
The quantity of protons identifies the element and cannot change; therefore, the neutron amount changes, ultimately changing the overall mass of the atom.
 
 C.
The sum of the electrons and neutrons equals the isotope's mass with the proton amount being given by the atomic number.
 
 D.
The sum of the protons and electrons equals the mas

anonymous · Answer

D.
The sum of the protons and electrons equals the mass of the isotope, and the neutron amount is equal to the atomic number.

anonymous · Answer

that is what it is suppose to b^ it got cut off

anonymous · Answer

Every element is supposed to have a certain proton number that is identical to the atomic number on the periodic table.
So same amount of proton and different amount of neutron changes the mass.

anonymous · Answer

so A

anonymous · Answer

??