**Correct option ****(D) 745 sq. units**

See Fig.

Since r^{2} + s^{2} = e^{2,} e = 31 or e = 19 is not possible. Therefore, e equal to 13, 20 or 25.

The possibilities for triplet {r, s, e} are {5, 12, 13}, {12, 16, 20}, {15, 20, 25}, {7, 24, 25}.

Since 16, 15 and 24 do not appear among any of pair wise differences of 13, 19, 20, 25, 31, we have a = 19, b = 25, c = 31, d = 20, e = 13.

Hence required area = 745 sq. units.