Final answer:
Skinfold calipers are used to estimate body fat by measuring the thickness of skinfolds at various locations on the body to determine body fat percentage. Option c.
Step-by-step explanation:
The tool used to estimate body fat via skinfold thickness is a. skinfold calipers. This method involves a health professional using calipers to measure the thickness of skin at various parts of the body. By comparing these measurements to standard values, an estimate of body fat percentage can be determined.
This is considered to be a simple, cost-effective, and relatively accurate method.
Other techniques for measuring body fat include b. bioelectric impedance, which uses electrical currents to estimate fat content, c. dual-energy X-ray absorptiometry (DEXA), which utilizes X-ray beams, d. air displacement within a bod pod, and e. underwater weighing, which assesses body density to calculate fat mass.
So option c.