Sodium Ions Are Single Atoms

Multiple Choice

Sodium ions are single atoms.Why can't they simply diffuse through the cell membrane's lipid bilayer?

A) Since they are charged,ions can't cross the hydrophobic center of the membrane without a channel or pump.
B) Sodium ions are covalently attached in groups of three,which are too large to diffuse easily.
C) Ions do traverse the membrane easily,but the sodium-potassium pump moves them back across.
D) Chelator proteins capture any ions that start to cross the bilayer.