How were most of the Americans who arrived in California before 1840 d

How were most of the Americans who arrived in California before 1840 different from the group of immigrants from the United States that arrived in after 1840?

A) The post-1840 group learned Spanish, converted to Catholicism, and became part of the local culture of Alta California.
B) The post-1840 group assumed Mexican citizenship.
C) The post-1840 group was more interested in making California part of the United States and retaining mainstream elements of American culture.
D) The majority of the post-1840 group lived mostly on large ranches spread along the coast.

ANSWER
Answer: C