The correct option is
B Spores
The life cycle and reproduction of the pteridophytes or ferns and their allies is characterized by a complete absence of conspicuous flowers and fruit, the production of minute fine spores, often in copious quantities, and by alternating generations of separate spore producing plants (sporophytes) and gamete producing plants (gametophytes). The general cycle involves the production of asexual spores on the sporophyte which are shed and germinate to grow into gametophytes which produce male organs with motile sperm and female organs with non-motile egg cells. Fertilization follows and the egg cell develops into a new sporophyte to complete and continue the cycle.
Hence, the correct answer is option B.