Which of the following is NOT a type of comb?

The correct answer identifies "Round comb" as a choice that is not a recognized type of comb in poultry. In poultry, combs serve various functions, including regulating body temperature and displaying health and vitality. Combs can come in several established varieties, each with distinct characteristics.

Single combs are characterized by a long, erect structure with a series of spikes running along the spine, while rose combs feature a flattened shape with small, rounded points. Cushion combs are distinct for their smooth, rounded appearance that resembles a cushion. However, "Round comb" is not an official category; thus, it does not fit within the established types of combs known in poultry classification. Understanding these different types can enhance showmanship skills and aid in proper breed identification.