In the Table Below Both Countries Produce at the Bold

Multiple Choice

In the table below both countries produce at the bold levels of output without trade.Assume the US and UK initiate trade and begin to completely specialize in the commodity in which they have a comparative advantage.What would the gains from trade be if the US trades 50 units of rice to the UK for 50 units of pudding?
Production Possibility Schedule for Rice and Pudding in the United States and the United Kingdom
$\begin{array}{|cc|cc|}\hline \text { United States } &&\text {United Kingdom } \\\hline \text {Rice} & \text {Pudding} &\text { Rice }& \text {Pudding} \\\hline 140 & 0 & 35 & 0 \\\hline 120 & 10 & 30 & 20 \\\hline 100 & 20 & 25 & 40 \\\hline 80 & 30 & 20 & 60 \\\hline 60 & 40 & 15 & 80 \\\hline 40 & 50 & 10 & 100 \\\hline 20 & 60 & 5 & 120 \\\hline 0 & 70 & 0 & 140 \\\hline\end{array}$

A) US: 10 units of pudding,20 units of rice
B) US: 20 units of pudding,10 units of rice
C) UK: 10 units of pudding,20 units of rice
D) UK: 20 units of pudding,10 units of rice