Why Did Southern Slaves Live in Better Conditions by the Mid-Nineteenth

Why did southern slaves live in better conditions by the mid-nineteenth century than those in the Caribbean and South America?

A) They did not; slaves led vastly healthier lives in regions other than the American South.
B) Southern Protestant churches encouraged better treatment of southern slaves than the Roman Catholic Church did with slaves in the Caribbean and South America.
C) The rising value of slaves made it profitable for slaveowners to take better care of them.
D) Laws in the South were far more protective of slaves than were laws concerning slaves elsewhere.
E) Southern slaves had a greater likelihood of becoming free than did other New World slaves.