In the 21st century, the countries of the world will either find a way to drastically reduce global carbon emissions, or it will likely face unprecedented environmental problems in relation to global warming.
A. the countries of the world will either find a way to drastically reduce global carbon emissions, or it will face unprecedented environmental problems in relation to global warming
B. the countries of the world will either find a way to drastically reduce global carbon emissions, or they will face unprecedented environmental problems relating to global warming
C. either the countries of the world will find a way to drastically reduce global carbon emission, or it will face unprecedented environmental problems relating to global warming
D. either the countries of the world will find a way to drastically reduce global carbon emission or face unprecedented environmental problems in relation to global warming
E. the countries of the world will either find a way to drastically reduce global carbon emissions or face unprecedented environmental problems relating to global warming
This question is based on Parallelism.
The sentence contains the correlative conjunctions – either-or.
To maintain parallelism of correlative conjunctions, each of the pair of conjunctions must be followed by a word of the same part of speech. For example, if ‘either’ is followed by a verb, so must ‘or’.
In Option A, ‘either’ is followed by the verb ‘find, and ‘or’ is followed by the pronoun ‘it’. Furthermore, the singular pronoun ‘it’ cannot refer to the plural antecedent ‘countries’. So, Option A can be eliminated.
In Option B, ‘either’ is followed by the verb ‘find’, and ‘or’ is followed by the pronoun ‘they’. The helping verb ‘will’ is also repeated unnecessarily. So, Option B can be eliminated.
In Option C, ‘either’ is followed by the noun ‘the countries’, and ‘or’ is followed by the pronoun ‘it’. While this doesn’t affect parallelism, the singular pronoun ‘it’ cannot refer to the plural antecedent, ‘countries’. So, Option C can also be eliminated.
In Option D, ‘either’ is followed by the noun ‘the countries’, and ‘or’ is followed by the verb ‘face’. So, Option D can also be eliminated.
Option E maintains parallelism. In this option, ‘either’ is followed by the verb ‘find’, and ‘or’ is followed by the verb ‘face’. Therefore, E is the most appropriate option.