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

(B)
- Stack with red block, yellow block, purple block, from bottom to top

(C)
- Stack with red block
- Stack with orange block
- Stack with yellow block
- Stack with green block

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