Assertion : The nitrogen-fixing bacteria in leguminous plant nodules live as symbionts. Reason : Leg-haemoglobin synthesized by leguminous plants protect bacteria.

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