Answer:
d. Symbiotic bacteria on the roots of legumes help supply nutrients to the plant.
Step-by-step explanation:
Symbiotic bacteria on the roots of legumes help supply nutrients to the plant by fixing atmospheric nitrogen done by nitrogen fixing bacteria. There are some bacteria present in the roots of plants which fixes atmospheric nitrogen and convert in available form to the plants and in exchange the plant provides food and habitat to the bacteria that performs nitrogen fixation.