What Experiment Disproved the Idea of Spontaneous Generation

What experiment disproved the idea of spontaneous generation?

A) Maggots did not appear on rotting meat wrapped in gauze, but did appear on meat in a closed jar.
B) Maggots appeared on meat wrapped in gauze, but not in a closed jar.
C) Bacteria randomly appeared in an open flask of sterilized broth.
D) Bacteria did not appear in an open flask of sterilized broth if the opening was faced downward so bacteria couldn't fall in.
E) This hasn't actually been disproven yet.