(A)
- Stack with yellow block
- Stack with blue block, purple block, from bottom to top
- Stack with red block, orange block, from bottom to top

(B)
- Stack with red block
- Stack with orange block, blue block, from bottom to top

(C)
- Stack with orange block
- Stack with red block, blue block, from bottom to top

(D)
- Stack with blue block
- Stack with red block, purple block, green block, orange block, from bottom to top