Evaluate the integral ∬Dxy dA\iint_D xy \, dA∬DxydA over the region DDD bounded by x=0,y=0,x+y=1x=0, y=0, x+y=1x=0,y=0,x+y=1.
124\frac{1}{24}241
16\frac{1}{6}61
112\frac{1}{12}121
18\frac{1}{8}81