Correct Answer:
C. A letter is being written by her
The question requires converting the sentence "She is writing a letter" into its correct passive voice form.
The original sentence is in the present continuous active voice, indicating an action happening at the moment of speaking. To convert a present continuous active sentence to passive voice, we follow the structure: object + is/am/are + being + past participle of the main verb + (by agent).
- C: A letter is being written by her. This is the correct passive voice. 'A letter' (the object) becomes the subject. The verb 'is writing' (present continuous active) correctly transforms into 'is being written' (present continuous of 'to be' + 'being' + past participle). The agent 'by her' is included as it specifies who is performing the action.
- A: A letter is written by her. This is in the present simple passive voice ('is written'), changing the tense from continuous to simple, which is incorrect.
- B: A letter was being written by her. This uses the past continuous passive voice ('was being written'), incorrectly shifting the tense from present to past.
- D: A letter has been written by her. This is in the present perfect passive voice ('has been written'), which is the wrong tense for the original continuous action.