Hearing improves in middle childhood because the tube in the inner ear that is often the site of ear infections in toddlerhood and early childhood has now matured to be longer and narrower than it was before. How does this help with ear infections?

Middle ear infections are the most common illness that brings children to a pediatrician and the most common cause of hearing loss in children. Adults can also get middle ear infection. The treatment of a middle ear infection depends on how bad the symptoms are and what's causing the infection. But as a child grows older from being a toddler to childhood stage, the middle ear gets longer and less prone to infection.

the answer for your question is b.

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