PRINCIPLES IN CORROSION - Which one of the following statements is correct

a)     In cathodic protection, corrosion of a metal is minimised by forming a contact to another metal with a higher reduction potential.

b)    In anodic inhibition, corrosion of a metal is minimised by forming a porous barrier at its surface.

c)     Iron corrodes more rapidly in salty water because the electrochemical potential is higher.

d)    Iron corrodes in oxygen-free water.