Which is the best experiment that disproves the Spontaneous Generation Theory?

a The experiment where microbes do not develop spontaneously in COVERED, HEATED nutrient fluids b The experiment where microbes do not develop spontaneously in COVERED, UNHEATED nutrient fluids c The experiment where microbes do not develop spontaneously in UNCOVERED, UNHEATED nutrient fluids d The experiment where microbes do not develop spontaneously in UNCOVERED, HEATED nutrient fluids e The experiment where microbes always develop in nutrient fluid