By default, when you add a new question to your survey, it is deactivated. Activate your survey questions to view them in preview mode and have them appear in the live survey after publishing. Do this by clicking the power button in the question modification toolbar. When the power icon is red, your question is deactivated. Clicking on it will prompt you for approval to activate the question. Once approved, the button will turn green and the question will be activated.
Note: If your survey has already been published with an activated question, deactivating that question in the portal will not remove it from the live survey. The changes will be reflected in the live survey only after that version has been published.