GMAT Sentence Correction (SC) | Re: Though the Pythagorean theorem is attributed to Pythagoras,

Hi ratinarace, answer choice B changes the meaning and doesn't work with the rest of the sentence. The proof of the Pythagorean theorem is what appeared in Euclid's work, not the theorem itself. The unclear pronoun "it" seems to be referring back to the theorem itself, not the proof. As such, it is incorrect (as is E which also uses the pronoun "it").

As for D vs C, I saw it more as a subtle difference in meaning. "The choices are really:

C. the
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