According to spontaneous generation concept life could come from nonliving things, such as mice from corn, flies from bovine manure, maggots from rotting meat, and fish from the mud of previously dry lakes. It is also called as abiogenesis. But several experiments have been conducted to disprove spontaneous generation. Biogenesis, panspermia and materialistic theory do not relate to spontaneous generation. Thus, the correct answer is option B.