Bacteria lives in the digestive systems of cows. the bacteria receive nutrients from the food the cows eats. this relationship is mutualism i've because the cows.

What is the tychonic system? a. a model of the solar system in which all the planets (including earth) orbit the sun b. a model of the solar system in which the planets, moon, and sun orbit earth c. a model of the solar system where the planets orbit the sun, and this system orbits earth d. a model where all the planets and earth are fixed in space and only the sun and moon move e. a model that expands the system to a vast number of galaxies and star systems