Sentence Correction

A letter by Mark Twain, written in the same year
as The Adventures of Huckleberry Finn were
published, reveals that Twain provided financial
assistance to one of the first Black students at
Yale Law School.

(A) A letter by Mark Twain, written in the same
year as The Adventures of Huckleberry Finn
were published,
(B) A letter by Mark Twain, written in the same
year of publication as The Adventures of
Huckleberry Finn.
(C) A letter by Mark Twain, written in the same
year that The Adventures of Huckleberry
Finn was published.
(D) Mark Twain wrote a letter in the same year
as he published The Adventures of
Huckleberry Finn that
(E) Mark Twain wrote a letter in the same year
of publication as The Adventures of
Huckleberry Finn that
need expln. for the correct ans

IMO answer is C

tom cud u pls provide your explanation for C its the OA

(C) A letter by Mark Twain, written in the same
year that The Adventures of Huckleberry
Finn was published, reveals that Twain provided financial assistance to one of the first Black students at
Yale Law School.

"written in the same....published," modifies "a letter."
So, read the sentence as if modifier wasn't there and it makes sense, A letter by Mark Twain reveals that....school.

what about the idiom same .. as in comparison with the idiom same .. that, which is used in option C????

Please explain