As the most enduring scripted series in TV history, ‘Friends’ has been entertaining families for 20 years, and while the jokes are a big reason for their longevity, so too are the scarily relatable  characters. 

As the most enduring scripted series in TV history, ‘Friends’ has been entertaining families for 20 years, and while the jokes are a big reason for their longevity, so too are the scarily relatable characters. 

A – while the jokes are a big reason for their longevity, so too are the scarily relatable characters. 

B – while the jokes are a big reason for its longevity, so too is the scarily relatable characters. 

C – a big reason for its longevity is not only the jokes but also the scarily relatable characters. 

D – while the jokes are a big reason for its longevity, the characters that are relatable are a big reason too. 

E – a big reason for their longevity is not just the jokes but the scarily relatable characters too.

Right Answer: C

Error Identification

Identifier	Error Type
Not only … but also	Parallelism
Their vs it	Pronouns
Are vs is	Subject Verb Agreement

Explanation: 

The primary identifier is that of ‘while… so to’ and ‘not only…but also’ in some of the options. There are other errors such as pronoun use that can also help us eliminate incorrect answers.

A – ‘their’ is incorrect since we need a singular pronoun to refer to ‘Friends’; ‘while’ and ‘so too’ is redundant.

B – ‘is the scarily…’ is incorrect as it doesn’t agree with the subject ‘characters’. ‘while’ and ‘so too’ is redundant.

C –  This fixes all the errors with the original sentence and is the correct answer. 

D – While the parallel construction is correct, the option introduces the clause ‘that are relatable on are a big reason too’. This is wordy and awkward. 

E – ‘their’ is incorrect as in (A).