Crotalaria juncea and Alhagi camelorum are commonly used as green manure in crop fields and in sandy soils. These plants have nitrogen-fixing properties, which can help enrich the soil with nitrogen and improve its fertility, making them valuable for agricultural purposes.
So, the correct option is (A): Crotalaria juncea and Alhagi camelorum
There are several valuable microorganisms that are beneficial to humans in various manners such as: