This sentence states two main facts about the construction of the army of terra-cotta warriors. It also describes the army of terra-cotta warriors.
WHAT ARE THE ERRORS IN THE ORIGINAL SENTENCE?
Rivaling the pyramids of Egypt or even the ancient cities of the Maya as an achievement, the army of terra-cotta warriors created to protect Qin Shi Huang, China’s first emperor, in his afterlife is more than 2,000 years old and took 700,000 artisans more than 36 years to complete them.
1) This sentence has one clause as shown. The sentence begins with a modifier “rivaling the pyramids…”.
2) This modifier modifies the subject “army of terra-cotta warriors”. The subject is then followed by another modifier “created to protect…”.
3) This subject has two verbs in parallel construction as shown. These two verbs indicate two facts about the “army of terra-cotta warriors”.
4) In this sentence, the use of pronoun “them” is unnecessary.
5) Furthermore, it does not agree in number with its antecedent. ”Them” refers to the subject of the sentence – “the army”. Since “army” is a collective noun, it is singular and hence the pronoun referring to it should also be singular.
6) Furthermore, the use is redundant as explained below.
7) Lets consider the sentence with only verb 2 and with the pronoun replaced by the noun it refers to:
The army of terra-cotta warriors took 700,000 artisans more than 36 years to complete the army of terra-cotta warriors.
As you can see the noun – army of terra-cotta warriors is unnecessarily repeated. Lets consider a simpler sentence to understand this better.
Process of elimination :-
Choice A: Pronoun redundancy error – "them"
Choice B: Pronoun redundancy error as in Choice A.
Choice C: No Errors
Choice D: Punctuation Error: The structure of this sentence is such that the subject for verb 2 in the original sentence is no longer “the army of terra-cotta warriors”. The subject is “700,000 artisans”. Hence this sentence now has two independent clauses but these are not connected using comma + and. These are connecting using only “and”. This is incorrect.
Choice E: Pronoun error as in Choice A. This choice is similar to choice A. The placement of verb modifier “to complete them” has been changed. Thus, Choice C is the correct answer.