The correct option is B 400 - 600
Seminiferous tubules are located within the testes for spermatogenesis. They are known as the functional unit of a testis. They are the site for the maturation and transportation of the sperm cells within the male testes. They are made up of Sertoli cells surrounded by spermatogenic cells. The total length is approximately 400-600 metres. Hence, the correct answer is option C.