GMAT Sentence Correction (SC) | The endurance and consistency of baseball star Lou Gehrig,

is the OA for this question A?

My reasoning:

(A) The endurance and consistency of baseball star Lou Gehrig, known as “The Iron Horse,” are legendary. - Endurance and Consistency as subject - are
(B) The endurance and consistency of Lou Gehrig, a baseball star known as “The Iron Horse,” is legendary. -Verb mismatch with Subject
(C) Known as “The Iron Horse,” the endurance and consistency of Lou Gehrig, the baseball star, is legendary. - Iron Horse should modify LG.
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