Aluminium is more reactive than iron. But aluminium is less easily corroded than iron because

Galvanized iron is coated with a layer of which metal?

When iron undergoes corrosion,it .........

Given below are two statements:
Statement $I$: Corrosion is an electrochemical phenomenon in which pure metal acts as an anode and impure metal as a cathode.
Statement $II$: The rate of corrosion is more in alkaline medium than in acidic medium.
In the light of the above statements,choose the correct answer from the options given below:

Metal can be prevented from rusting by

Assertion : Copper metal gets readily corroded in an acidic aqueous solution.
Reason : Free energy change for this process is positive.