The correct answer is the Know-Nothing Party.
The 1840's and 1850's saw a significant increase in America, especially from Germany and Ireland. This mass immigration was caused by several different factors including a potato famine in Ireland and political revolutions in Germany.
These immigrants were not received well by some citizens, as Americans feared that these individuals would take jobs from Americans. This resulted in increased nativist sentiment and the Know-Nothing Party. The Know-Nothing Party was one based on anti-immigrant sentiment and helping to pass laws that restricted immigration into the US.