Bulbil is also called as bulblet. It is a tiny secondary bulb that forms between a leaf and stem or in place of flowers on certain plants. In some plants, the bud develops into bulbil instead of a flower. It separates from the parent plant and given rise to a new plant. Therefore, it is a vegetative reproduction e.g., Agave Oxalate. 

Underground stem modifies into bulbs, corms, rhizomes, stolons, and tubers.

Leaf bases are modified into Leaf-Pitcher to catch insects.
Therefore, the correct option is C.