Correct option is B
The sphincter muscles are responsible for controlling the exit of waste material from the body. These muscles are circular muscles that can contract and relax to control the flow of materials through various openings in the body.
Sphincters are specialized muscles that surround and close an opening in the body, maintaining control over the passage of substances like urine, feces, or bile.
The most well-known sphincters in the body are the anal sphincter, which controls the expulsion of waste, and the urinary sphincter, which controls the release of urine from the bladder.
The sphincter muscle works as a voluntary or involuntary control mechanism, depending on the sphincter’s location in the body.
Pectoralis: The pectoralis muscles are located in the chest and are primarily involved in the movement of the arms.
Rectus: The rectus muscles (like the rectus abdominis) are involved in abdominal movement.
Gastrocnemius: The gastrocnemius is a calf muscle involved in movement.