Final answer:
To straighten the ear canal in a child under 3, the pinna should be pulled downward and backward, which allows for proper examination during otoscopic procedures.
Step-by-step explanation:
To straighten the ear canal in a young child under 3 years old, the pinna should be pulled downward and backward. This is the correct technique for otoscopic examination in a young child, allowing a clear view of the ear canal and tympanic membrane. Pulling the pinna upward and backward is the technique used for older children and adults, but for a young child, it is important to remember that their ear canal is shaped differently, and the appropriate manipulation involves a downward and backward motion.