Kam kara  I chose json format since the structure and format of the responses are not a consistent structure. Basically, it makes it more simple to store the data. A questionnaire could have a few questions and then many answers or many questions and just a few answers each. If you were to create a table-based response, then you would need to almost mimic the structure of the questionnaire where you have a responses table which has many question_responses and the question responses has many answer_responses (since it could me multiple choice). Then you need to worry about the type of response for the answer where the some of them may be a boolean, string, or text and picking the correct type when storing the response.