An estimated 50,000 slaves escaped as a direct impact of: lax laws relating to slave ownership mismanagement of the transportion of slaves the underground railroad human rights campaigns in the south.

An estimated 50,000 slaves escaped as a direct impact of The Underground Railroad. The Underground Railroad was a network of hiding places and secret routes that enabled African-American slaves to escape. It led them to either Canada or a free state. This network was not literally an "underground railroad" but a resistance that was hidden from public knowledge.   

Ibelieve the answer is (a) true.