Final answer:
The continental divide in North America is high land that separates rivers flowing westward and eastward, which corresponds to option B.
Step-by-step explanation:
In North America, the continental divide refers to the line of the highest points that marks the separation between rivers flowing eastward and westward. Therefore, the correct answer to the question is B. high land that separates rivers that flow west from rivers that flow east. This divide runs along the spine of the Rocky Mountains and other associated ranges, stretching from Alaska in the north to Mexico in the south. Rivers to the west of this line flow to the Pacific Ocean, while those on the east flow to the Atlantic Ocean or the Gulf of Mexico.