Legumes are plants that produce .

Nitrogen

Explanation:

Legume roots produce their own nitrogen, which is a major fertilizer nutrient needed by all plants for growth. Nitrogen is produced in nodules that form on the roots of legumes, which contain Rhizobium bacteria. The bacteria take nitrogen from the air and convert it into a form the plants can use.

The answer is Nitrogen

answer; /// i believe the correct answer is (reactants);

the answer u all are looking for is 4000000000000000000000 million years.