In the following question on Active and Passive Voice, transform the sentence "A police constable arrested the burglar just before dawn" into the correct passive form by choosing the best alternative.

Introduction / Context:
This question tests your understanding of how to change a simple past tense sentence from the active voice to the passive voice in English grammar. In many competitive exams, such voice transformation items are common because they check whether you can preserve tense, meaning, and time expressions while changing the focus of the sentence. The original sentence focuses on the doer of the action, a police constable, whereas the passive form must correctly focus on the receiver of the action, the burglar. You also need to keep the time expression just before dawn in a natural and meaningful place in the sentence. The option that satisfies all these conditions is the correct answer.

Given Data / Assumptions:
The key information can be summarised as follows.

• The original active sentence is: A police constable arrested the burglar just before dawn.
• The verb arrested is in the simple past tense.
• Subject in the active sentence: a police constable.
• Object in the active sentence: the burglar.
• Time expression: just before dawn, which must be retained without changing the meaning.

Concept / Approach:
To change an active sentence to the passive voice, we make the object of the active sentence the grammatical subject in the passive sentence. The verb is converted to the appropriate form of be plus the past participle of the main verb, keeping the tense unchanged. The subject of the active sentence is optionally retained in a by phrase, which shows the agent who performed the action. In this question the tense is simple past, so the passive auxiliary should be was or were, followed by the past participle arrested. The time expression just before dawn should be kept in a natural position, usually at the end of the sentence, and the logical meaning of the arrest should remain exactly the same.

Step-by-Step Solution:

Verification / Alternative check:
We can verify the correctness by mentally converting the passive sentence back into the active form. If we start from The burglar was arrested by a police constable just before dawn and ask who performed the action and whom it affected, we get the original relationship: a police constable arrested the burglar just before dawn. The tense remains simple past, the meaning is unchanged, and the time expression is preserved. This confirms that the transformation is correct. Any variation that changes the tense, swaps subject and object, or alters the time reference is grammatically or logically incorrect.

Why Other Options Are Wrong:
Option A uses is arrested, which is simple present, so it does not match the simple past arrested in the original sentence. Option C also uses is arrested and therefore has the same tense error. Option D completely changes the meaning by suggesting that the police constable was arrested by the burglar, which reverses the roles of subject and object. Option E uses past continuous was arresting, which again changes the tense and suggests an ongoing action rather than a completed one just before dawn. Thus, only option B accurately reflects the original sentence in passive voice.

Common Pitfalls:
Candidates often forget to keep the tense the same when changing voice, and they mistakenly use is or was being instead of the correct auxiliary. Another common error is to accidentally swap the roles of subject and object, which can completely reverse the meaning. Some learners also misplace time expressions like just before dawn, resulting in sentences that sound unnatural. To avoid these problems, always identify subject, verb, object, and adverbials first and then systematically apply the passive voice rules. Check that the resulting sentence can be converted back to the original active form without any change of meaning.

Final Answer:
The correct passive form is: The burglar was arrested by a police constable just before dawn.