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Nilanjan Bhowmick AIR 3, CSIR NET (Earth Science)
Saurabh 1
This one also you can solve using the concept of Bowen's reaction series. As you already know the fact that, first mineral that will form melt or will melt first is quartz from the silicate magma and last one (melt)will be of Olivine . Taking reverse conditions of what we have done for melting, then clearly in case of crystal formation, olivine will win the race and it will crystallize first and then pyroxene and then amphibole and so on. Now in the options, you can surely leave options C and D. Now remaining two options(A&B) , both are pyroxenes. Diopside is a clinopyroxene and Enstatite is orthopyroxene. Out of these two, Enstatite will be the first one to form crystal or will get crystallized. So, correct answer is B.