Question

From the 1830s on, people hoping to settle in the Northwest A-were stopped by the Cumberland Gap. B-traveled along the Oregon Trail. C-followed a trail blazed by Zebulon Pike. D-were stopped by the Great Plains.

Answer 1

Generally speaking, from the 1830s on, people hoping to settle in the Northwest "B-traveled along the Oregon Trail," since this had become a well-established route.