The correct answer for this question is "Epiglottis". The Epiglottis is responsible for cutting off the passage way to the airway while swallowing/eating food to prevent the food from being inhaled by the body.The Epiglottis has a leaf-like shape structure with a cartilage that covers the passage way into the air ways of the body.
Answer:
Symbiosis and metabolic cooperation.
Explanation:
Symbiosis is a term called for bacteria that live in symbiosis with another organism or with each other, as we can see here there is a tow bacteria living in the same place (gut), one attached to the surface of the gut and another one synthesize ATP which can be used by other bacteria which made both of them benefits from a metabolic reaction that made by one bacteria.
A, c, b i think. good luck!