I'm writing a series of verbal questions for the interactive GMAT site, Magoosh, which will go live next month for the verbal section. Currently, I'm writing SC questions that I hope are at the 700+ level. Any feedback would be appreciated. Thanks!



Metamorphic rocks form when a protolith, which can come in the form of an igneous, sedimentary, or a previous metamorphic rock, is subjected to intense pressure and heat, sometimes in excess of 200 degrees Celsius.

(A) Metamorphic rocks form when a protolith, which can come in the form of an igneous, sedimentary, or a previous metamorphic rock, is subjected to intense pressure and heat, with temperatures exceeding 200 degrees Celsius.
(B) A protolith, which forms from igneous, sedimentary, or previous metamorphic rocks, when subjected to intense pressure and temperatures exceeding 200 degrees Celsius becomes a metamorphic rock.
(C) Metamorphic rocks result when a protolith, which can be an igneous, sedimentary, or previous metamorphic rock, is subjected to intense pressure and heat, a process in which temperatures can be in excess of 200 degrees Celsius.
(D) Metamorphic rocks result when a protolith, which can be igneous, sedimentary, or previous metamorphic rocks, is subjected to intense pressure and heat, sometimes in excess of 200 degrees Celsius.
(E) Forming from igneous, sedimentary, or previous metamorphic rock, a protolith is subjected to intense pressure and heat—sometimes in excess of 200 Celsius—to become a metamorphic rock.