Spontaneous generation is the idea that a living thing can arise from nonliving material. This idea was a prevailing theory up until the late 1700s. What most likely caused this theory to be discarded? A. a series of experiments showed that living things only arise when other living things reproduce B. a series of experiments showed that nonliving materials are covered in microorganisms C. ideas in the late 1700s became old-fashioned and scientists looked for new, fresh ideas D. research in the field of biology proved that most living things reproduce sexually