A conditional block looks at the slug you’ve set for it and presents different content based on the different answer variants you created for your segmenting question.
If you use the default header message, for example, you enter default header text that will be displayed if no match is made, then the text for a match and a corresponding header text for each variant you want to handle with a different header message.
When the header is displayed, the current user’s qna (answer) field is searched for text that matches the identifiers you’ve entered in the block editor and when a match is found, the corresponding header text is displayed.