Best approach to building a Workflow which ould feature different combinations of four choices?

Does that mean that each option (A, B, and C), have their own image? If so, I would create a separate list/library that contains all the images, corresponding with the choices a user can select.

The workflow will then, via a single action, collect the selected options by the user. For each option, it will query the image and put the images in another collection/dictionary within the workflow. That will also enable you to use the same workflow if you get more choices.

If you need more help, please let me know!

Sorry @Michel  I should have been clearer, I meant 'you get the picture' as a turn of phrase. I've solved the problem by having a Review Request action. In that action I'm using a Nintex form and I've added a checkbox with corresponding text fields. I've added a rule not(control) which hides the control if it isn't selected and that appears to be doing the job!

 

Thanks for the reply @Michel