Really good question sir.
NOT always a pronoun, in this case "this" or they or it has a clear antecedent. Ther are also several example also on the GMAT SC.
So, the question is: what can we do in such scenario ?
The context of the sentence. The key is the sentence as a whole.
Even though in this case is quite clear the antecedent which is the vihuela.
the vihuela of 15th-century Spain. A skilled guitarist would likely be able to pick up this (iii) _______ instrument, also an ancestor of the viol, and competently play a tune.
Piece by pice we do have
1) the instrument dated back in Spain during the 1400
2) A skilled guitarist would pick this ?? and this is what ??
Pick up Spain as a country or the period of time, the 15th century, does not hold any water
So the person picks up this - s/he would pick up THAT instrument aforementioned. what else should s/he pick ??
Also, the guitarist picks up what ?? a beautiful watch, an amazing ball.....whatever it is
In the blank must go an adjective: tall, small, ugly........and so forth
This is another hint this refers to if this musty be followed by an adjective, the same cannot be avant-garde
What if I do not know if avant-garde is an adjective or less ?? My intuition: usually an adjective is a single word: amazing, blurry......here we do have a composite word.
Therefore, this refers to an instrument and that instrument must be archaic which means very old
Tell me if now is clear sir
and this
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