In the history of cell biology, what was Francesco Redi's key contribution that influenced later ideas about cell theory and the origin of life?

• A. He identified the nucleus as a common feature of plant and animal cells.
• B. He proposed that all cells arise from pre-existing cells ("Omnis cellula e cellula").
• C. He used controlled experiments with meat in open and sealed containers to show that maggots arise from flies’ eggs rather than spontaneous generation.
• D. He first observed cells in cork using a compound microscope and coined the term "cell".

Answer: (C)