In the following question on voice, choose the option that best expresses the sentence "The kids were laughing at the old lady." in Passive voice.

Introduction / Context:
Voice change questions test your ability to convert a sentence from Active voice to Passive voice or vice versa without changing its basic meaning or tense. Here the active sentence "The kids were laughing at the old lady." must be rewritten in Passive voice. The focus is on choosing the correct tense (past continuous) and keeping the preposition "at" in its proper place.

Given Data / Assumptions:

• Active sentence: "The kids were laughing at the old lady."
• Subject in the active sentence: "The kids".
• Object in the active sentence: "the old lady".
• Main verb phrase: "were laughing at".
• We must express this idea in Passive voice with correct grammar and tense.

Concept / Approach:
To change from Active to Passive voice, the object of the active sentence becomes the subject of the passive sentence. The tense of the main verb must be preserved. "Were laughing" is past continuous (was/were + present participle). In Passive voice, past continuous becomes "was/were being + past participle". We also keep the preposition "at" after the verb "laughed", because in English we say "laugh at someone". Therefore, the passive structure must be "was being laughed at by..."

Step-by-Step Solution:
Step 1: Identify the object "the old lady" in the active sentence. In Passive voice, this becomes the subject: "The old lady...".Step 2: Recognise the tense "were laughing" as past continuous. The corresponding passive auxiliary structure is "was being" (for singular subject).Step 3: Change the main verb "laugh" to its past participle "laughed".Step 4: Retain the preposition "at" because the verb phrase remains "laughed at".Step 5: Add the agent "by the kids" to show who performed the action.Step 6: Combine these to get: "The old lady was being laughed at by the kids."

Verification / Alternative check:
We can test the correctness by reversing the transformation. Starting from "The old lady was being laughed at by the kids", convert back to Active voice: subject becomes "The kids", past continuous passive "was being laughed at" turns into "were laughing at", and the object becomes "the old lady". This gives exactly the original sentence: "The kids were laughing at the old lady." This confirms that option B preserves both tense and meaning.

Why Other Options Are Wrong:
Option A ("The old lady is laughing at the kids.") reverses the roles and even changes the tense to present continuous, so it is not a valid voice change. Option C ("The old lady was being laughed by the kids.") omits the preposition "at", which is necessary in English usage; we say "laughed at someone", not "laughed someone". Option D ("The old lady was laughed at by the kids.") is grammatically possible but corresponds more closely to simple past "The kids laughed at the old lady" rather than past continuous "were laughing". It therefore does not preserve the aspect of ongoing action.

Common Pitfalls:
Candidates often forget to keep the same tense when changing voice, especially with continuous forms. Another common error is dropping necessary prepositions like "at" after verbs such as "laugh" or "look". A reliable method is to first identify the tense and aspect (simple, continuous, perfect), then apply the appropriate passive pattern: "am/is/are being", "was/were being", "has/have been", etc. Finally, ensure that required prepositions stay with the verb in the new sentence.

Final Answer:
The correct Passive voice form is "The old lady was being laughed at by the kids."