The Question of Whether the Killing/letting Die Distinction Is Morally

The question of whether the killing/letting die distinction is morally relevant can be posed by asking whether we are equally to blame for allowing people in Third World countries to starve as we would be for
)

A) killing them by sending poisoned food.
B) refusing to give them the money they need to purchase food.
C) withholding medicine that they need to survive.
D) depriving them of knowledge they need to produce food.