A : Azotodesmic lichens are biofertilisers enriching nitrogen contents in soil.
R : This ability is due to the presence of heterocystous blue-green algae as phycobiont component.
A. If both assertion & reason are true and the reason is the correct explanation of the assertion
B. If both assertion & reason are true but the reason is not the correct explanation of the assertion
C. If assertion is true statement but reason is false
D. If both assertion and reason are false statements
