Show correct answer on review quiz for Hotspot question (Storyline 360)

Storyline will automatically show a Review layer when review a quiz. You can add a layer with that exact name yourself. Or Storyline will add it if you enter any text in the Post-quiz review field when you're editing the question in Form View. 

Note: When Storyline creates the Review layer, it automatically gives it the layout of the "Review" Feedback Master. But you can edit that, as needed. (https://community.articulate.com/series/articulate-storyline-360/articles/articulate-storyline-360-user-guide-how-to-use-feedback-masters  )

Put whatever info you want on the Review layer to indicate the correct answer to the hotspot question.