Final answer:
Scarlett can use a pentagonal prism with one pentagon and five rectangles to design the candy package.
Step-by-step explanation:
Scarlett can use a pentagonal prism with one pentagon and five rectangles to design the package for the candy her company makes. The pentagonal prism has a pentagon for the base and five rectangles as the lateral faces. This shape provides a unique and visually interesting design for the candy package.