The correct answer is option (C) Francesco Redi.
Spontaneous generation was a theory putforth proposing that living organisms came into life from non-living matter. It was hypothesized that fleas arise from the dust or the maggots could arise from dead flesh. In 1668, Francesco Redi challenged this concept by setting up a major experiment. He placed meat in a sealed, open and partially covered container with gauze. After few days he observed that the maggots appeared only on the meat in the open jar and not on the meat in the other two containers. Thus, disproving the concept of spontaneous generation. This was again proved by the swan neck experiment of Louis Pasteur in the year 1859.