Which of the following is an unstructured question?
A. "What are the most important characteristics for choosing a brand of shampoo?"
B. "How satisfied were you with your last shampoo purchase: very unsatisfied, unsatisfied, neutral, satisfied, or very satisfied?"
C. "Were you happy with the quality of the shampoo you purchased (Yes/No)?"
D. "On a scale from 1 to 5 (with 1 being very unimportant and 5 being very important), how important is fragrance when choosing a shampoo?"
E. "How many brands of shampoo have you purchased in the past year: 0, 1, 2, 3, 4, 5, or more than 5?"
Answer: A. "What are the most important characteristics for choosing a brand of shampoo?