Final answer:
The sides of a thermoforming mold are tapered to aid in the removal of the part, and this taper is called draft.
Step-by-step explanation:
The correct answer is A) Draft. In thermoforming, which is a manufacturing process used to shape plastic sheet materials, the sides of the mold are tapered to aid in the removal of the part.
This taper is called draft. The draft angle allows for easier ejection of the molded part from the mold without damaging or sticking to the mold surface.