What Hypothesis Was Being Tested in the Initial Experiment with Open

What hypothesis was being tested in the initial experiment with open versus sealed jars?

A) Spontaneous generation is more likely during the long days of summer.
B) The type of meat used affects the likelihood of spontaneous generation.
C) Maggots do not arise spontaneously,but from eggs laid by adult flies.
D) Spontaneous generation can occur only if meat is surrounded by air.