Assertion. `HNO_(3)` renders iron passive.
Reason. Iron reacts with `HNO_(3)` to form ferric nitate.
A. If both assertion and reason are true, and 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 both assertion and reason are false