Answer:
Dear, professor their name I am concerned about a grade I received. For our lastest assignment I received a D. I understand your grading but as it has dropped by grade I was hoping to fix it. I am concerned that stress from my courses and work affected this project though I feel I worked hard. I would love a chance to repair my assignment, if this is not possible I would I like to review with you. Thank you for your time.
Sincerely, your name