] At the beginning of the 20th century, the bison, more informally known as the buffalo, was almost extinct in North America. [2] In way off from the 30 to 60 million bison that once roamed American prairies prior to the late 1800s. [4] the return of the bison is something for which all North Americans can be thankful. Which word provides the best transition between sentences 3 and 4 ?