Elevated Levels of ACTH Can Cause Skin Darkening,as a Result $\alpha$

Elevated levels of ACTH can cause skin darkening,as a result of the ability of ACTH to:

A) Bind to the melanocortin 1 receptor (MC1R) .
B) Stimulate cortisol production.
C) Bind to the corticotropin-releasing hormone (CRH) receptor
D) Stimulate adrenal androgen production.
E) Stimulate $\alpha$ -melanocyte-stimulating hormone ( $\alpha$ -MSH) production