Why did settlers begin using the trail identified in this map? A. people needed to ship goods from west to east.
B. gold was discovered in Oregon.
C. explorers were searching for a water route to the Pacific Ocean
D. the government offered people free land in Oregon

D. The government offered people free land in Oregon.

Explanation:

in 1803 the louisiana purchase took place, doubling the size of the country. by 1840 almost 7 million americans had migrated westward in hopes of securing land and being prosperous. the belief that settlers were destined to expand to the west is often referred to as manifest destiny.

explanation:

a.impressment of us soldiers