Fish (thousands of pounds per year) .5.............z...\".........:............. .......... ..................................................................... ............................................................... ........... French?\" --------- 0 IOO 200 300 400 500 Wheat (thousands of bushels per year) 20) The gure above shows the production possibilities frontiers for the United Kingdom and France. United Kingdom and France spend half of their time producing sh and wheat. After specialization, suppose that France decided to keep 300 of wheat and trade the rest. Given that the terms of trade (measured by the number of sh divided by the number of wheat) is 1, the gain to France of sh with specialization and trade is: A) 50 of sh B) 100 of sh C) 200 of sh D) zero of sh