Ayo help me please

How did American settlement in the Oregon Country change starting in the 1840s?
A. Fewer settlers came as the California Gold Rush drew most settlers.
B. As the British established control over the region, fewer Americans came.
C. Missionaries and settlers joined the fur traders who went there in earlier years.
D. Disease and conflict with Native Americans made settlement more difficult.

American settlers began to arrive from the east by the Oregon Trail starting in the early 1840s, and came in increasing numbers each subsequent year. Increased tension led to the Oregon boundary dispute. Both sides realized that settlers would ultimately decide who controlled the region. if u copy and paiste u could be expelled but here you go