Why is my grade a zero for a quiz?
Answer
This can happen if you get disconnected and thus are unable to click on Submit all and finish. If you had saved your work periodically by clicking on Save without submitting then your instructor will at least be able to recover some of your answers when the quiz's available-until date has passed, via a regrade.
You should contact your instructor to determine the best way to proceed; (s)he may allow multiple attempts, or may offer to reset your attempt so you can retake the quiz.