Respuesta :
In 1850s, the main occupation of the people arriving in Oregon and California is gold mining. Thus, the answer is letter B. In May of 1848, a newsletter proclaimed about the gold mines found in the lands and many people from the neighboring places flocked to the place.
Gold mining was the main occupation for people arriving in California and Oregon in the 1850s.
What is California Gold rush?
This was a period in the 1850s in which gold was found by James W. Marshall at Sutter's Mill.
This led to people migrating to the area to explore it and they consisted of mostly gold miners.
Read more about California Gold rush here https://brainly.com/question/1346705
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