Is there supposed to be a picture for this?
B - the lion eats the grass—it cannot be A. because grass gives off o2 not co2
Well, flowers give insects like bees and butterflies nectar. That's their food. In return, the insects spread the flower's pollen so that other plants like its type can be fertilized.
This is mutualism - a symbiotic relationship were two organisms benefit.
Happy to help!