Final answer:
The correct position of a hair tool to achieve minimal volume and no scalp curl is holding it at a 90-degree angle to the scalp, often used to create a smoother appearance with slight body.
Step-by-step explanation:
In hairstyling, the tool position that results in no curl at the scalp and a minimal degree of volume is achieved by holding the hair tool (such as a curling iron or brush) at a 90-degree angle (perpendicular) to the scalp. This technique is often used to create a smoother look with slight body rather than tight curls or pronounced volume at the roots. It is important for students of cosmetology or those learning hair styling techniques to understand the effects of tool positioning on the resulting hairstyle.