Select the option that expresses the given sentence in passive voice.
1. A letter was written by Shiva to the head of the HR department in response to the advertisement.
2. A letter was written by the head of the HR department to Shiva in response to the advertisement
3. A letter was wrote by Shiva to the head of the HR department in response to the advertisement.
4. A letter had been written by Shiva to the head of the HR department in response to the advertisement.
The correct answer is option 1. A letter was written by Shiva to the head of the HR department in response to the advertisement.