Hotspot Auto-Submit

A custom hotspot question can be a solution as Rod points out. However you need to know that:

• To reproduce all the features of the default hotspot question slides, it will take knowledge of advanced actions.
• Reporting a score to a LMS is not a real problem (see link below)
• If you are talking about a responsive Fluid Boxes project you need to know that in a normal Fluid Box it is impossible to use a click box nor a transparent shape button because of the stack limitation. The only possibility is than to cut your image in parts (I use SVGs in that case because an SVG as button can have any shape, contrary to click boxes and shape buttons) as you may see in the example here:

http://blog.lilybiri.com/svgs-for-custom-hotspot-question

The workflow can also be used for click boxes or non-visible shape buttons.

Quiz questions require the user to click the Submit button to indicate they are ready to have their answer evaluated.

If you don't want any Submit button involved, why not just set up a normal slide with a Click Box or Smart Shape button  (set to 0 opacity) as your hot spot?  You can set the hit object to have a success score reported to the quiz.  This allows you to execute an action immediately when the learner clicks the correct area.