Question

bison or buffalo?
bison and buffalo belong to the bovidae, or cattle, family, but they are different species and have distinct characteristics. many people refer to the creatures that once roamed the american west as buffalo; however, these animals are actually american bison, and they are only found in north america. on the other hand, two species of buffalo—the cape buffalo and the water buffalo—are found in africa and asia, respectively. unlike the american bison, which has short horns similar to those of cows, buffalo have broad, sweeping horns. in addition, the american bison has a broad head carried low and a massive hump at the shoulders. in contrast, buffalo dont have shoulder humps and their heads are smaller than the bisons.
what is the main, or central, idea of the passage?
american bison are often mistakenly called buffalo, but the two creatures are quite different.
american bison can be distinguished from buffalo by the size and shape of their horns.
buffalo and american bison are both members of the bovidae family.

Explanation:

The passage starts by stating bison and buffalo are different species in the Bovidae family. It then explains the common misnomer of American bison as buffalo, and details their differences in habitat (American bison in North America, buffalo in Africa/Asia), horn shape, head size, and presence of shoulder humps. The first option captures the main idea of the misnaming and the distinctness, while the other options focus on single aspects (horns or family membership) which are supporting details, not the central idea.

Answer:

A. American bison are often mistakenly called buffalo, but the two creatures are quite different.