A nurse researcher working in a subacute orthopedic hospital floor. She notes that her elders ...

A nurse researcher working in a subacute orthopedic hospital floor.
 
  She notes that her elders with knee replacements sleep as many as 16 hours a day, waking only for physical therapy and meals, but she also notices that those with many visitors sleep fewer hours and seem to experience more pain. She wonders whether sleep in elders after knee replacement prevents pain, or whether elders select the coping strategy of sleeping more, in response to pain, and begins to attempt to identify the relationship between the two. A literature search reveals only three descriptive studies on this topic, one quantitative and two qualitative. What is the relationship between elders' hours of sleep following knee replacement and its relationship with report of pain?
  a. The research aim
  b. The research purpose
  c. The research problem
  d. The research topic