Assertion : Root nodules in leguminous plants are inhabited by Anabaena.
Reason : Laguminous plants are an example of symbiotic nitrogen fixation.

Options

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

Answer

A

Explanation

Symbiotic bacteria are protected from oxygen by inhabiting a plant host. Bacteria of the genus rhizobium inhabit the root nodules of leguminous plant other symbiotic association but are less important. Anabena Azollae a nitrogen fixing cyanobacterium lives in the pores on the fronds of a water ferm called Azolla. This symbiotic partnership is used to enrich rice paddies with organic nitrogen.