Will and Grace Have Adjoining Unfenced Back Yards and Each

Will and Grace have adjoining unfenced back yards and each has just adopted a new puppy.Will values a fence between their yards at $250 and Grace values a fence between their yards at $200.The value of the effort required to build the fence is $300,which will be split equally if they both help build the fence.If one of the neighbors begins building the fence the other might or might not come over to help.Therefore,their payoff matrix is $\begin{array}{c}\quad\quad\quad\quad\quad\quad\text { Will }\\\text { Grace }\begin{array}{|c|c|c|}\hline& \text { Build } & \text { Not Build } \\\hline \text { Build } &\text { Grace: } \$ 50 ; \text { Will: } \$ 100 & \text { Grace: }-\$ 100 ; \text { Will: } \$ 250 \\\hline \text { Not Build } & \text { Grace: } \$ 200 ; \text { Will: }-\$ 50 & \text { Grace: 0; Will: } 0 \\\hline\end{array}\end{array}$
Will's dominant strategy in this game is to

A) build the fence.
B) help build the fence if he observes Grace starting to build it first.
C) not build the fence.
D) alternate between helping Grace and not helping her.