Why did many pioneers travel the california trail after 1848?
to find rich farmland
to gain religious freedom
to mine for gold
to trade with mexico

(i think its c but in don't know)

Many pioneers traveled the California Trail after 1848 to mine for gold.

Explanation:

The California gold rush was a social phenomenon occurred in the United States between 1847 and 1855, characterized by the large number of immigrants who came to the vicinity of San Francisco (California) in search of that metal. This phenomenon began near the town of Coloma, when gold was discovered in Sutter's Mill. When the news of the discovery spread, around three hundred thousand people emigrated to California from the rest of the United States and other countries.

answer; taking up arms to defend the nation;

the group i'm selecting: greeks.

a first group of greek immigrants came to the us in the 1850s. the second group came to america starting in the 1890s due to economic opportunities they didn't have back in their home caused by the hardships of ottoman rule. greek immigration was 90% male, many of them expected to work and return to greece after earning enough capital, but ultimately had to remain in the us after the greek genocide.