The Table Below Shows Hypothetical Canadian Domestic Demand and Supply

The table below shows hypothetical Canadian domestic demand and supply schedules for granite.Assume there are no restrictions on trade.
TABLE 32-6
-Refer to Table 32-6.At what price and quantity combination will Canada not engage in international trade in granite?

A) $1000 and 20 tonnes
B) $1000 and 170 tonnes
C) $700 and 80 tonnes
D) $400 and 140 tonnes
E) $400 and 0 tonnes