Assertion : In Millikan's experiment for the determination of charge on an electron, oil drops of any size can be used. Reason : Millikan's experiment determine the charge on electron, by simply measuring the terminal velocity.

• A.    If both assertion and reason are true and the reason is the correct explanation of the assertion.
• B.    If both assertion and reason are true but reason is not the correct explanation of the assertion.
• C.    If assertion is true but reason is false.
• D.    If the assertion and reason both are false.
• E.    If assertion is false but reason is true.