URGENT Mormon pioneers established Salt Lake City in 1847, shortly before the area became part of the United States. The town was important to westward expansion because it was
A.
the first major settlement located within the land ceded by Mexico.
B.
the first major settlement located within the Oregon Territory.
C.
the only major settlement between the Mississippi River and the Rocky Mountains.
D.
the only major settlement between the Rocky Mountains and the Sierra Nevada.