Specifically, Q1 asks respondents to check all products that they own. In Q2, I want to present only that list and ask them to choose the product they are most familiar with. So not only does the list in Q2 have to be only those that were selected in Q1, but I also don’t want to even show Q2 if they only choose one response in Q1.
The first part of your question is easy. You can pipe in the answers from previous questions into followup questions. Review the SurveyGizmo documentation for details – https://help.surveygizmo.com/help/option-piping
The second part of your question – hiding q2 – is much more difficult. You would have to write a custom script to accomplish this.
Our approach would be to ‘hide’ q2 by default and then let the script unhide it if there was more then one responses to q1. If there was only one answer to q1, the script would have to set that value as the answer to q2.