In the following question on the Active and Passive voice, choose the correct passive form of the sentence: The owners remodelled the car to help it sell.

Introduction / Context:
This question tests understanding of the change from Active voice to Passive voice in English grammar. In many competitive examinations, candidates must recognise not only the correct passive structure but also tense consistency, appropriate auxiliary verbs, and natural wording. The given active sentence uses the simple past tense and expresses an action performed by the subject the owners on the object the car, with an infinitive phrase to help it sell explaining the purpose of the action. The task is to select the passive sentence that preserves this meaning while maintaining smooth and correct English.

Given Data / Assumptions:

• Active sentence: The owners remodelled the car to help it sell.
• Tense: simple past.
• Subject: the owners.
• Object: the car.
• Purpose clause: to help it sell.
• We must convert this into an accurate passive sentence.

Concept / Approach:
In voice change, the object of the active sentence becomes the subject of the passive sentence. The main verb remodelled in simple past becomes was remodelled in the passive. The original subject the owners is introduced with the preposition by. The purpose infinitive to help it sell remains unchanged because it is not the main verb of the sentence but only expresses intention or purpose. A correct passive construction should therefore be The car was remodelled by the owners to help it sell, which retains tense, agent, and meaning accurately.

Step-by-Step Solution:

Verification / Alternative check:
Check tense and meaning of the original and the chosen passive. The original sentence describes a completed action in the past; therefore, the passive must also use past tense was remodelled, not present continuous is being remodelled. Also, the purpose should remain clear and natural in English. The phrase to help it sell is idiomatic and widely used. If we changed it to to help it being sold, the sentence would sound awkward and ungrammatical. Thus, the best passive form that satisfies tense, structure, and idiom is The car was remodelled by the owners to help it sell.

Why Other Options Are Wrong:

• Option B uses is being remodelled, which changes the tense from past to present continuous and therefore does not match the original meaning.
• Option C uses had phrase to help it being sold, which is grammatically unnatural because help is normally followed by a bare infinitive, for example help it sell.
• Option D combines present continuous is being remodelled with the incorrect form to help it being sold, so it has both tense and structure errors.

Common Pitfalls:
Learners sometimes focus only on replacing remodelled with was remodelled while ignoring the tense of the whole sentence. Another common mistake is to overcomplicate the infinitive phrase and produce forms like to help it being sold, which are not standard English. When changing voice, always preserve the original tense and aspect, shift the object to subject position, and keep purpose or reason clauses intact unless there is a compelling grammatical reason to adjust them. Reviewing common collocations such as help it sell can prevent awkward or incorrect constructions.

Final Answer:
The car was remodelled by the owners to help it sell.