Answer: D. Chromium
Chromium is the supplement that is used to promote weight loss and improve muscle development.
Explanation:
Chromium refers to a mineral that is needed for human health. Small amount of chromium is needed in human body. It is of two forms namely: trivalent chromium and hexavalent chromium. It is taken by mouth for weight loss and improvement of muscle development. It is also used or taken to improve athletic performance, increase energy, and prevention of age-related mental decline.