ABCD is a square and M and N are the midpoints of BC and CD respectively. Then sinθ=
[asy]
draw((0,0)--(2,0)--(2,2)--(0,2)--cycle);
draw((0,0)--(2,1));
draw((0,0)--(1,2));
label("A", (0,0), SW);
label("B", (0,2), NW);
label("C", (2,2), NE);
label("D", (2,0), SE);
label("M", (1,2), N);
label("N", (2,1), E);
label("θ", (.5,.5), SW);
[/asy]
<spanclass=′latex−bold′>(A)</span>55<spanclass=′latex−bold′>(B)</span>53<spanclass=′latex−bold′>(C)</span>510<spanclass=′latex−bold′>(D)</span>54<spanclass=′latex−bold′>(E)</span>none of these