Which of the following is a common symptom of an ear infection?

Ear pain is a common symptom of an ear infection, as it is typically caused by inflammation and buildup of fluid in the middle ear. This inflammation irritates the ear structures, leading to discomfort or pain sensation. Infections can result from various factors, such as bacteria or viruses, which cause the fluid to accumulate and create pressure within the ear canal, resulting in pain.

Ringing in the ears, balancing problems, and vision changes may occur in some cases, but they are not as directly associated with ear infections as ear pain. While ringing in the ears (tinnitus) can be related to ear issues, it is not the primary symptom of an ear infection. Balancing problems may arise if the inner ear is affected, but this is less common. Changes in vision are not typically linked to ear infections. Thus, ear pain is the most recognized and common symptom that signals the presence of an ear infection.