Which Experiences a Greater Effective Nuclear Charge, an Electron in the Outer

Multiple Choice

Which experiences a greater effective nuclear charge, an electron in the outer shell of neon (atomic number 10) or an electron in the outer shell of sodium (atomic number 11) ?

A) sodium because it contains more protons
B) neon because of less inner shell shielding
C) sodium because it contains a greater number of shells
D) neon because it is a smaller atom