MikeScarn , the quotation in your signature is hilarious.

Ah, the lovely dangling modifier issue.
In three of the options, the introduction is "dangling"
because the subject that the intro clause should modify is
not in the subsequent phrase or clause.

The introduction is a subordinate clause with a HE in it, a fact that means
the next thing we ought to be reading about is a man or a boy.

The sentence means that
Don Knotts played many memorable characters in the 50 years that he was on television, but his portrayal of the bumbling Deputy Fife on "The Andy Griffith Show" was the role that earned him lasting fame and five Emmy awards.

Split #1: The pronoun he should modify Don Knotts

Even though "Don Knotts" comes after the pronoun "he," the man himself is still the antecedent.

Option A incorrectly makes he modify both the show and the actor's portrayal.
A TV show is not a HE. An actor's portrayal of a character is not a HE.

Options B and E incorrectly makes the actor's portrayal the target of the modifier "Although he played . . ."
A portrayal of a character is not a HE.
Do not be fooled: possessive words are adjectives. They describe the noun.
They are not the noun.
Don Knotts' is not a noun. HIS is not a noun. Don Knotts' is not a HE. HIS is not a HE.

Eliminate A, B, and E

• Split #2: keep meaning and logic clear by keeping the sequences of phrases clear

After we see the word "portrayal," we expect to hear the answer to the
question, "The portrayal OF WHAT character or OF WHOM?"

True, the portrayal happened on "The Andy Griffiths" show.
But the show did not earn Knotts immortality or five Emmys.
Don Knotts' portrayal of Barney Fife earned him those things.

Portrayal of should be followed immediately by Barney Fife, as in option C.

Option D's insertion of "on the A.G. show" between "portrayal" and "of Barney Fifte"
is neither warranted nor stylistically preferred.

Eliminate D.

The correct answer is C.
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