Hi Luc Baeten,
Thank you for your interest in Sitefinity 4.0.
Unfortunately the forms module does not have such functionality. To achieve the feature with the images you will have to create custom forms control which inherits from the default one (FormMultipleChoice). The easiest implementation would be to assign the image as a CSS rule for each label which is rendered next to the choice.
The second option can be achieved with adding layout controls or directly assingning CSS classes to each widget you drop on the form and jQuery. For example you drop a multiple choice control on the form. Then go to its editor and from the Appearance section you set the CSS class. For each control you will do this and your theme will set those css classes to be display: none. Then you can use the Generic Content block to put some an html link or button control which when clicked will use jQuery to toggle the display of each question. See attached screencast.
You can even use the jQery approach for appending images. You will get the jQuery object with class lets say .question1, then you will get all of its children elements and append images with CSS.
the Telerik team
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