Stefanie's hamstrings are classified as skeletal muscles, which are under voluntary control and crucial for movement. Unlike cardiac and smooth muscles, skeletal muscles allow for precise movements in activities such as running and jumping. Understanding the role of skeletal muscles is important for anyone involved in physical training. ;
Stefanie's hamstrings are classified as skeletal muscles, which are essential for voluntary movement around joints. They allow actions such as bending the knee and moving the thigh, making them vital for physical activities. Therefore, the correct answer is D) skeletal muscles.
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