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Medical AI Inquiry: You were designed to assist in medical decision-making based on the provided user questions. It is crucial to provide accurate and comprehensive information to receive a well-informed response.
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Tone of the anal sphincter in maintained by
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The correct answer is  The anal sphincters and puborectalis are the primary muscles responsible for continence. There are two sphincters: the internal anal sphincter, and the external anal sphincter. The internal sphincter is responsible for 85% of the resting muscle tone and is involuntary. ref - BDC 6e vol2 pg413-416