Final answer:
The patient, who is an adolescent, is most likely developing puberty-related gynecomastia due to hormonal changes which are common in this stage of development.
Step-by-step explanation:
Considering the context of the patient's age, which is an adolescent, the client is most likely developing puberty-related gynecomastia. Conditions such as acute otitis media are more common between the ages of 3 months and 3 years. Impetigo is a contagious skin infection, and scoliosis usually manifests as posture asymmetry and may be diagnosed during adolescence, but it does not specifically relate to puberty changes. Gynecomastia during puberty is fairly common and is due to hormonal changes. This condition is temporary and typically resolves on its own over time. It typically resolves without treatment, but it is always important to rule out other causes.