Explanation

The sentence is explaining why the exhibition of the painter’s work was unsatisfactory, and since it says that the painter’s talents were real, the word in the blank has to indicate why those talents were not, in the opinion of the author of the sentence, good enough. The words “limited” and “circumscribed” do so and also produce sentences that are alike in meaning, so this pair forms the correct answer.

Although “undiscovered” and “hidden” are similar in meaning, they do not make sense in the context of the sentence, since they do not indicate why the painter’s talents were not adequate. Other choices, such as “partial” and “prosaic” might make sense in context, but none of the other choices that meets that criterion also has a companion choice that would produce another sentence alike in meaning.

Thus the correct answer is limited (Choice A) and circumscribed (Choice D).
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The key word here is BUT.
This suggests a shift in the nature of the adjectives used to describe the painter's talents.
We're told the painter has REAL talents (which is a positive thing), so the word after but must be a NEGATIVE words.

I predict NOT SO GOOD for the blank.

Check the answer choices....

A limited (has a NEGATIVE connotation...KEEP)
B partial (this could be negative, but it seems out of place when describing talents. However, it's not bad. Let's KEEP for now)
C undiscovered (not negative....ELIMINATE)
D circumscribed (this is the same as LIMITED, so it's a nice match with A...KEEP)
E prosaic (this means BORING, which is negative....KEEP)
F hidden (not negative....ELIMINATE)

After the first round, we're left with: limited, partial, circumscribed and prosaic
Since PARTIAL and PROSAIC have no synonyms, we can ELIMINATE them.

Answer: A & D

Cheers,
Brent
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a nd d

I don't understand why limited and partial cannot be answers to this. They are also synonyms.

If you look at these 4 words - limited, partial, prosaic and circumscribed, they seem to fit in the sentence individually and satisfy the context.
Now comes the essence of sentence equivalence, where we want pair of words that:
1. obviously fit the context, and
2. make sense together as a pair i.e. if you alternate the words in the pair, meaning pf the sentence doesn't change.

Lets leave "prosaic" - as it doesn't have a companion for the pair. There are 3C2 i.e. 3 possible combinations => (limited, partial) ; (partial, circumscribed) ; (limited, circumscribed)

1. From a synonym strength perspective, (limited, circumscribed) rank higher. Though (limited, partial) can be thought to convey the meaning of "incomplete", they are not strong synonyms especially compared to (limited, circumscribed)
2. And, you are using these words as adjectives to describe "talents". "limited" generally goes with talents, not "incomplete" (incomplete conveys something is not complete, here "talent" is not complete but wrt to what?)

A,D

I got A and E. I don't like D.

Circumscribed means limited in the sense that it is limited by something else - an externally administered limit. Look at example sentences with the word circumscribe inside:

"Their autonomy, it is true, was carefully circumscribed."
"Otherwise, each had separately recognized, the future was circumscribed."

Seems to me like 99% of the time, the passive voice is used for this verb, and this is because there is an unstated subject providing the limit. These sentences make it clearer:

"In the middle of the drawing was a circle circumscribed by a square."
"The church's role was tightly circumscribed by the new government."

Source for the sentences is Longman Dictionary.

So to describe a persons talents as circumscribed is confusing because there is no externally acting force suppressing it - they just have a limit. A tree that grows alone in a field doesn't have 'circumscribed' growth - it has all the space and resources it needs to grow, but it just doesn't. It would also sound extremely strange to say its growth was 'circumscribed' by its DNA.

On the other hand to describe talent as 'prosaic' is to indicate that it is not outstanding, ordinary and akin to others. Seems much more suitable in this context to me.