Which action increased the tensions between the north and south that led to the civil war?

The main issue that started the Civil War was the slave trade. The North didn't think African Americans should automatically be slaves and thought owning slaves was morally wrong. However, the South disagreed and believed African Americans were lesser beings and therefore should be enslaved. The slave legislation was probably the action that increased the tensions the most.

A ) Large numbers of settlers moved to California

Explanation: