For each row write the lowest element to the right, and for each column write the greatest element below the matrix

maximum {-3,-4,-1} = -1, minimum {2,-1,6,7} = -1. There exists an equilibrium pair (3rd row, 2nd column). The number -1, which lies in the intersection of 3rd row and 2nd column, is the lowest in the 3rd  row, is the greatest in the 2nd column. Answer is D.