Select the option that expresses the given sentence in passive voice.
Ramu has been delivering letters to these villagers ever since he was fifteen years old.
1
Letters had been delivered to these villagers ever since Ramu was fifteen years old.
2
Letters had been delivered to these villagers by Ramu when he was fifteen years old.
3
Letters are delivered by Ramu to these villagers since he was fifteen years old.
4
Letters have been delivered to these villagers by Ramu since he was fifteen years old.