The Figure Below Shows Arcticland's Annual Production Possibilities Boundary for the Production

The figure below shows Arcticland's annual production possibilities boundary for the production of fish and ice.
FIGURE 33- 4
-Refer to Figure 33- 4.Suppose that a trading partner offers to give Arcticland ice in exchange for its fish.If Arcticland is to improve its consumption possibilities,the terms of trade must be 1 tonne of ice for:

A) 2 tonnes of fish.
B) 3 tonnes of fish.
C) 1 tonne of fish.
D) 0.33 tonne of fish.
E) 0.5 tonne of fish.