One of the ingredients used to make bread is yeast, a type of microorganism. this may seem odd, to use a microorganism as an ingredient, but the yeast serves an important function. in this case, how would you describe this microorganism? a) yeast is a harmful microorganism that produces gas. b) yeast is a beneficial microorganism that the bread rise. c) yeast is a beneficial microorganism that keeps the dough clean. d) yeast is a harmful microorganism that may cause illness in humans.