Rhino populations are threatened by poachers hunting them for their horns. Rhino horns are made of what material?

A Bone
B Keratin
C Cartilage

Keratin is a fibrous protein material. Despite it being commonly found in the world — it also makes up hair and fingernails — rhinos are hunted for their horns, which are sold for use in ornamental carvings or touted as having medicinal properties.

The correct answer is Keratin.