Are open-ended questions that enable respondents to reply in their own words. unstructured questions double-barreled questions leading questions loaded questions double negative questions

The correct answer is the first option,  unstructured questions.unstructured questions refer to questions that are open-ended, flexible and mimic natural conversation. with these types of questions, researchers avoid influencing the respondent's answers, and the respondent is free to express him or herself freely and in detail. unstructured questions researchers gain deep insights into the topic being researched. 

It's most likely choice a, it makes the most sense in my opinion.