Can the Atomic Mass of an Element Change

Multiple Choice

Can the atomic mass of an element change?

A) No,it is fixed.If it changes at all then you have formed a different element.
B) Yes.Adding or losing electrons will substantially change the atomic mass.
C) Yes.Adding or losing protons will change the atomic mass without forming a different element.
D) Yes.Adding or losing neutrons will change the atomic mass without forming a different element.