Is it D

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.

Its between B and E. Though I can't see an error in E, B sounds good. IMO B

IMO A. Tough Q indeed. Dont hav much clues

B - changing the meaning. It seems when igneous, sedimentary, or previous metamorphic rocks are subjected to pressure and heat, then a protolith is formed

C- Can be cannot be used here, as 200 degree celsius is a required condition

D- 200 degree should be explicitly modify temperature(not present) or should be present with heat, not pressure and heat both

E same as D

Whats the OA

IMO D.

I eliminated B, C and E and chose between A and D.

Option A and the question do not match

I'd choose the original sentence.
Note, I'm not saying A because its NOT the original sentence.

dendude wrote:I'd choose the original sentence.
Note, I'm not saying A because its NOT the original sentence.

What does "in excess of 200 F " in the original sentence modify. This cannot be used for heat. So original sentence is wrong anyways..

Although B changes the meaning but seems to be the most suitable

This question was flawed from the beginning with the mismatch between the underlined part and (A). Below is the corrected version. Nobody chose the correct answer, so let's try this one more time. I'll post the answer with explanations after I get a few replies.



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, sometimes in excess of 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 exceed 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.

C??

I would go with B.

Here's why:

Eliminate A, D, and E since "in excess of 200 degrees Celsius" is unidiomatic. With B and C, choice C seems to suggest that the "process" of intense heat and pressure involves "temperatures can exceed 200 degrees Celsius," which is awkward; intense heat and pressure isn't a process, and there is no prerequisite for such a "process" to involve temperatures exceeding 200 degrees Celsius.

i will go with B as well...
looks the most apt

IMO E

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. Meaning changed
(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. Awkward construction
(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.

B is wrong because it changes the meaning

C is the best option!