Show Web Object only when learner clicks on button

Actually, my layers are intended to illustrate triggers that "makes the student open the web object for an incorrect answer."  Use them as models to build what you want. If you want the learner to click submit, and immediately see the review if their answer is wrong, follow the pattern of layer 1 for your Incorrect layer. If you want them to get a message that says they have answered incorrectly, then click an object, then see the review, use the pattern of layer two for your trigger. Either way, you can put the appropriate actions on the built-in Incorrect layer.

If, as you say, each one goes to a different review page, then yes, you need one for each question. Besides, it is better pedagogical practice to make feedback immediate, so you don't want to wait until the end to give the review.