What Decision Should Be Made Under Minimax Regret

Short Answer

$$\begin{array} { | l | c | c | c | } \hline & s _ { 1 } & s _ { 2 } & s _ { 3 } \\\hline \mathrm { d } _ { 1 } & 250 & 750 & 500 \\\hline \mathrm { d } _ { 2 } & 300 & - 250 & 1200 \\\hline \mathrm { d } _ { 3 } & 500 & 500 & 600 \\\hline\end{array}$$
What decision should be made under minimax regret?