Assessment questions are always multiple choice (single or multiple correct answers), and are exactly the same as those you use for knowledge checks. So, you can gradually build-up a bank of questions for either use.
Overall feedback on the whole assessment always occurs at the end. This feedback includes a scorecard with the learner's percentage of accuracy and whether this percentage constitutes a pass or fail. For both outcomes, the learner can click thebutton to display all the questions, with the answers chosen, and whether the answers were correct or incorrect.
You do not need to add feedback topics per question. So, if you do reuse questions from knowledge checks, you do not need to add their feedback topics. When the learner runs the course assessment, the WBT also ignores any in-topic feedback within reused question topics.