Hello @JenniferMcClure
This is a great question! I did some testing for you on this and wanted to share what I found.
If you are using Build On Last Attempt and a quiz question that requires manual grading (such as Essay or File Upload) you will need to go into speedgrader and mark the question as correct, using the Check-Mark button, or incorrect using the X button. Marking the question as correct will tell Canvas that this is an acceptable response from the student and does not need to be re-administered on the students next attempt.
If you mark the essay question as Incorrect, the students can begin their additional attempt and retry the essay question again. One cool part of Build On Last Attempt is that the students response to the essay question they submitted originally, appears in the text box when they begin the quiz again, which allows them to edit their response and fine tune grammar and such.
HERE is the product blog post for the Build On Last Attempt functionality available for New Quizzes.
Feel free to test it out and experiment in Student View if you have a sandbox.
Hopefully this helps!
-Colton
