Researchers Are Interested in Improving Crop Plants to Enable Them

Researchers are interested in improving crop plants to enable them to form a symbiotic relationship with nitrogen-fixing bacteria.What genes would you need to transfer to a plant that does not associate with rhizobia to enable it to do so?

A) genes responsible for the synthesis of flavonoids and receptor for Nod factors
B) genes responsible for the synthesis of Nod factors and receptor for flavonoids
C) receptor for Nod factors and leghemoglobin gene
D) genes responsible for the synthesis of Nod factors and receptor for flavonoids and leghemoglobin gene
E) None of the above is sufficient,since many more genes need to be transferred.