(a) Seeds with wings are dispersed by wind. Due to the winged structure, the wind can easily blow off these seeds to different locations.
Example: seeds of drumstick, maple

(b) Small and light seeds can be dispersed by wind, or water. The light weight of seeds allows them to float on water, or be carried away by wind.
Example: light seeds of grasses

(c) Seeds with spines/hooks get attached to the bodies of animals. Thus these seeds are dispersed by animals to different places.
Example: Xanthium, Urena