Suppose a Delegate from the North at the Constitutional Convention

Suppose a delegate from the North at the Constitutional Convention is trying to convince his fellow Northern delegates to allow the South to count slaves as free persons. Which point should this delegate make to support his argument?

A) Allowing slaves to count as free persons is only fair to the Southern states.
B) Doing so would lead to the quick abolition of slavery in all the states.
C) Counting slaves as free persons would increase the amount of taxes Southern states would pay.
D) The health of the economy depends on exports from the Southern states.