Which Statement Is TRUE of the Sudanese Slave Trade and the Actions

Which statement is TRUE of the Sudanese slave trade and the actions of human rights groups?

A) Slave redemption programs are more effective with perfectly elastic supply.
B) Slave redemption programs can reduce the net number of slaves held in captivity but only by increasing the number of people who get enslaved.
C) Slave redemption programs can reduce the net number of slaves held in captivity by decreasing the demand for slaves.
D) Slave redemption programs are ineffective because the demand for slaves is perfectly inelastic, meaning that higher prices of slaves do not affect the quantity demanded.