1. mid-ocean ridges, which contribute to the process of sea-floor spreading, form as a result of

Mid-ocean ridges, which contribute to the process of sea floor spreading, form as a result of hot solidifie magma. There are no options given in respect to the question. I hope this is the answer you were looking for. This magma is formed from the decompressed melting of rocks of the upper mantle region. It mainly comes out between the gaps of the fault lines
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