Assertion : A.U. is much bigger than `Å`.
Reason : A.U. stands for astronomical unit and `Å` stands from Angstrom.
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.