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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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Which of the following aoic arches regress during development:
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The correct answer is  The aoic sac contributes a branch to each new arch as it forms, giving rise to a total of five pairs of aeries. (The fifth arch either never forms or forms incompletely and then regresses. Consequently, the five arches are numbered I, II, III, IV, and VI Ref: Langman's embryology 11th edition Chapter 12.