Usable (mobile) user interface for adding quizzes and selecting a correct answer

I am creating an administration panel for an application and one of the needs is to manage quizzes in one page without any pop-ups.

The application should be usable both on mobile and desktop.

I had come up with a solution to show buttons next to each possible answer of a question and the green checkmark indicates the correct answer. When a user would hover one of the red crosses - they would turn into green checkmarks, which would indicate that the user has to click to make this answer the right one.

However hover doesn't work on mobile. What could be an alternative solution good for user experience that would also be usable on a phone?