How does a researcher identify a problem that is suitable for doctoral research?

How does a researcher identify a problem that is suitable for doctoral research? In your initial post for this discussion, due no later than Day 3 of Week 2, explain the process of identifying a researchable problem, and support your assertions with specific citations from the literature and from your readings. Describe how you have gone about identifying a researchable problem associated with your research topic. If you aren`t certain about your researchable problem, identify what you are considering as a problem to address in your research.