[SOLVED] Which of the following statements is true about the term research hierarchy in EBP?

Which of the following statements is true about the term research hierarchy in EBP?

1. Tightly controlled experiments reside at the top, regardless of the EBP question.
2. Qualitative studies are the most likely to reside at the top for most EBP questions.
3. Where a type of study resides on a research hierarch depends on the type of EBP question being asked.
4. All types of research designs are relevant to all types of EBP questions.