Mona was writing a letter to her father
Verified Answer
A. A letter was written to her father by Mona.
B. A letter has been written to her father by Mona.
C. A letter was being written by Mona to her father.
D. A letter was written by Mona to her father.
Explanation:
The active sentence is in the past continuous tense ('was writing'). The passive voice for past continuous is 'was/were being + past participle'. Therefore, 'A letter was being written by Mona to her father' is the correct passive form.