The Table Below Shows the Payoff Matrix in the Form

The table below shows the payoff matrix in the form of short term profits for two firms,A and B,for two different strategies,investing in new capital or not investing in new capital.Payoffs are in millions of dollars. $\begin{array}{c}\quad\quad\quad\quad\quad\quad\quad\quad\quad\text { Firm B }\\\text { Firm A }\begin{array}{|l|l|l|}\hline & \text { Invest } & \text { Not Invest } \\\hline {\text { Invest }} & \$ 20 \text { for } \mathrm{A} & \$ 70 \text { for } \mathrm{A} \\& \$ 20 \text { for } \mathrm{B} & \$ 5 \text { for } \mathrm{B} \\\hline {\text { Not Invest }} & \$ 5 \text { for } \mathrm{A} & \$ 50 \text { for } \mathrm{A} \\& \$ 70 \text { for } \mathrm{B} & \$ 50 \text { for B } \\\hline\end{array}\end{array}$
Refer to the figure above.An industrial spy comes to firm B and offers to pay B in exchange for B's certain and enforceable promise to not invest.How much must the spy pay B?

A) $0.
B) At least $15 million.
C) At least $35 million.
D) At least $50 million.