Answer:
A. All cells come from pre-existing cells
Step-by-step explanation:
Francesco Redi's experiments aimed to test spontaneous generation, where life could emerge from non-living things. His first round included two groups of jars with raw meat in it. He covered one group with a thin cloth, allowing only air to get in, and the other group was left open.
In the jars left open, he noted maggots were present and the one that was covered contained no maggots.
The results indicated that the maggots only formed because flies laid their eggs on it and maggots developed. He did note that some maggots developed on the cloth itself, but on the outside.
Thus, he contributed in disproving spontaneous generation by showing that maggots only developed from the eggs that flies laid. This supports that all cells come from pre-existing cells.