Final answer:
Cotton grass seeds, which are attached to fluffy "cotton" hairs, are primarily dispersed by wind, a process known as anemochory.
Step-by-step explanation:
Cotton grass (Eriophorum) produces small seeds that are attached to a fluffy mass of "cotton" hairs. These seeds are most likely dispersed by wind. Members of the genus are known for producing copious quantities of seeds, each packaged in a cottony tuft of hairs which aid in dispersal. This method of seed dispersal is known as anemochory, which is common among plants like dandelions and other grasses, where lightweight seeds are carried away by the wind. This adaptation allows the seeds to travel over large distances, thereby increasing the plant's chances to colonize new areas.