The Graph Shown Demonstrates the Domestic Demand and Supply for a Good

The graph shown demonstrates the domestic demand and supply for a good, as well as a tariff and the world price for that good. If the economy was previously in autarky, the decision to open to trade and impose a tariff will cause the economy to:

A) increase its output from 250 units to 500 units.
B) decrease its output from 815 units to 500 units.
C) increase its output from 500 units to 815 units.
D) decrease its output from 1,500 units to 1,150 units.