Final answer:
a) Referred pain
The child complaining of pain in the right lower back while hospitalized with pneumonia is likely experiencing referred pain, a phenomenon where pain from an internal organ is felt in a different area.
Step-by-step explanation:
The child's first report of feeling pain in the right lower back after being hospitalized with pneumonia and initially not experiencing pain might suggest referred pain. Referred pain is the conscious perception of visceral sensations projected to a different region of the body. It is not random and is generally believed to occur because of shared neural pathways by which the brain misinterprets the pain originating from an internal organ, such as the lungs in the case of pneumonia, and projects it to other parts of the body.