Final answer:
The nurse would advise the mother to bring the baby in for a medical evaluation due to his consistent crying and pulling at his ear.
Step-by-step explanation:
The nurse would respond by saying, "That means his ear hurt. Bring him in to be checked."
This is the appropriate response because the baby's consistent crying and pulling at his ear are common symptoms of an ear infection. The nurse advises the mother to bring the baby in for a medical evaluation to determine the cause of his discomfort and provide appropriate treatment.