The number in each box below is the product of the numbers in the two boxes that touch it in the row above. For example, 30=6×5. What is the missing number in the top row?[asy]
unitsize(0.8cm);
draw((-1,0)--(1,0)--(1,-2)--(-1,-2)--cycle);
draw((-2,0)--(0,0)--(0,2)--(-2,2)--cycle);
draw((0,0)--(2,0)--(2,2)--(0,2)--cycle);
draw((-3,2)--(-1,2)--(-1,4)--(-3,4)--cycle);
draw((-1,2)--(1,2)--(1,4)--(-1,4)--cycle);
draw((1,2)--(1,4)--(3,4)--(3,2)--cycle);
label("600",(0,-1));
label("30",(-1,1));
label("6",(-2,3));
label("5",(0,3));
[/asy]<spanclass=′latex−bold′>(A)</span>2<spanclass=′latex−bold′>(B)</span>3<spanclass=′latex−bold′>(C)</span>4<spanclass=′latex−bold′>(D)</span>5<spanclass=′latex−bold′>(E)</span>6