Answer:
I believe it is A. Money
Chirsitanity is just a religion and doesn't really have anything to do with a better life or freedom. Laws wouldn't help them have a better life- In fact, the laws at that time were agains't slaves having freedom.
Thus, Money makes the most sense because they can buy their way out of slavery and buy a new home in a northren state or in Canada. Also, they can buy good food and clothes.
Hope this helps