Change the indirect speech to direct speech:
They informed their teacher that they had completed their project before the deadline.
1
They said to their teacher, "We have completed our project before the deadline."
2
They said, "They had completed their project before the deadline."
3
They said to their teacher, "You have completed your project before the deadline."
4
They told their teacher, "We had completed our project before the deadline."
5
Question Not Attempted