What is the color of the small sphere that is behind the largest cube?
return cubes ;return the   size of #1 ;return #1 where #2 is  the   largest ;return spheres ;return #4 that  are small ;return #5 that  are behind #3 ;return the   color of #6
['select', 'project', 'comparative', 'select', 'filter', 'filter', 'project']