Colorado Esthetician Written Practice Exam 2026 – Comprehensive All-in-One Guide for Exam Success!

The correct answer is A because the muscular system covers, shapes, and holds the skeletal system in place. Muscles are responsible for movement, posture, and producing heat in the body. They work in conjunction with the skeletal system to allow for movement and support the body's structure. Option B is incorrect because not all muscles are involuntary; there are voluntary muscles as well. Option C is incorrect because the primary responsibility of the muscular system is not to distribute oxygen and nutrients throughout the body, that is the function of the circulatory system. Option D is incorrect because the muscular system is not primarily responsible for protecting the body from external harm; it mainly focuses on movement and support.