Which erosional process primarily shapes valley floor profile following glacial retreat from a cirque?

💡 Explanation

When a glacier retreats from a cirque, exposing the valley floor, the meltwater forms a rejuvenated fluvial system because newly exposed, unweathered rock provides a steeper gradient, enhancing downcutting. Therefore, a rejuvenated fluvial system is more impactful than other processes which play secondary roles requiring specialized geographic and mechanical circumstances.

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