Assertion : Nitogen - fixing bacteria in legume root nodules survive in oxygen - depleted cells of nodules.
Reason : Leghaemoglobin completely removes oxygen from the nodule cells.
A. If both Assertion and Reason are true and Reason is the correct explanation of Assertion.
B. If both Assertion and Reason are true but Reason is not the correct explanation of Assertion.
C. If Assertion is true but Reason is false.
D. If both Assertion and Reason are false.