Thomas Jefferson, the muted public speaker, was quite different from

OFFICIAL EXPLANATION






This question turns almost entirely on appositive phrases.
An appositive is usually a noun modifier that renames a noun or describes the noun in another way.
Essential or "vital" phrases should not be set off by commas because commas indicate that the words are not essential to the meaning of the sentence.

Thomas Jefferson is renamed as "the muted public speaker" and "the firebrand author of the Declaration of Independence."

This construction may seem weird, but it is correct and forceful:
Muhammad Ali the boxer was very different from Muhammad Ali the imprisoned conscientious objector to the Vietnam War.
The construction means that Muhammad Ali behaved one way in the boxing ring and in another way in the "outside world."
We use the construction in the italicized sentence because that construction packs rhetorical punch (it is rhetorically forceful).

• Split #1: do not use commas with essential appositive phrases

If appositive phrases are required to understand the meaning of the sentence, we cannot set them off with commas.
Let's see what happens when we remove appositive phrases set off by commas in options A, B, and C.

A) Thomas Jefferson, the muted public speaker, was quite different from Thomas Jefferson, the firebrand author of the Declaration of Independence.
→ → Jefferson was quite different from Thomas Jefferson.

B) Thomas Jefferson, the muted public speaker, and Thomas Jefferson, the firebrand author of the Declaration of Independence, were quite different.
→ →Thomas Jefferson and Thomas Jefferson were quite different.

C) Thomas Jefferson, the muted public speaker, and Thomas Jefferson, the firebrand author of the Declaration of Independence, was quite different
→ → Thomas Jefferson and Thomas Jefferson was quite different.

When we remove the appositive phrases, the sentences do not make sense, so the phrases should not be surrounded by commas.

Eliminate A, B, and C

• Split #2 - Meaning

I am going to avoid the verb issue in option E because it's controversial.

Option E impermissibly uses "different" without a comparative word (different from whom or from what?).

Option E uses "different" in an informal way.
The sentence in (E) means that Thomas Jefferson was weird.
(I think that he was weird, but we cannot say so with this construction on the GMAT.)

E) Thomas Jefferson [appositive 1 and appositive 2] was different.
On the GMAT, be sure that "different" is coupled with either a stated or obvious comparative object.

Eliminate option E.

The best answer is D.

Not all modifiers set off by commas are removable in the strict sense.

Take a look at this official question.
Some people might argue with me, but I think that the sentence would lose its core meaning if we were to remove the material set off by commas.
Although the official sentence breaks the rules and sets off essential material with both "which" and commas, the sentence is acceptable because there's really no other way to write that very effective sentence in quite the same way.

I tried to rewrite option D in a way that maintained the rhetorical "flourish."
I did not think my rewrites were as effective as D.

This question also tests strategy.
We can guess from options A, B, and D that essential appositives are being tested.

We have no way to choose between A and B.
They are very similar—too similar.
Option D is nearly identical to option A. The words are identical but the commas have been removed.

Option E is a train wreck.
Option C uses the wrong verb.
Time to get strategic.

We can try the "odd man out" strategy (actually do choose the "odd man out"):
We can't choose between A and B.
Choose D.

Alternatively, we might try to figure out what is different (D contains the same modifiers as options A, B, and C, but option D lacks commas)—and that difference might spark thoughts about essential modifiers.
You may not be certain that apposition can be written this way (it can), but "almost certain" is good enough.

COMMENTS

These answers range from well-reasoned but not quite right to very well-reasoned and spot on.
If I were an aspirant, I would read this thread.
The best answers all use different language to explain the concepts; read about the issue in as many ways as you can.

Smiley faces go to well-reasoned but incorrect answers and kudos go to well-reasoned and correct answers.