Sucker
Stolon
Offset
Runner
Regeneration of new plants from the vegetative parts of the parent plant is called vegetative propagation or vegetative reproduction. Vegetative propagation is done with the help of vegetative parts such as roots, stem or leaves. The offset of Pistia helps in vegetative propagation. Pistia is a floating aquatic plant. The stem forms offsets, that is grows parallel to the surface of water and forms roots and leaf system at intervals. So, the correct answer is option C.