C. Traction apophysitis (Osgood-Schlatter disease): This condition is characterized by inflammation of the patellar tendon at its insertion on the tibial tubercle, often seen in adolescents involved in sports activities. The patient's age, symptoms (pain worse at the end of practice), and physical examination findings (point-tenderness about the tibial tubercle) are consistent with this diagnosis.

Overuse injury or strain: Given the patient's involvement in basketball, overuse of the knee could lead to strain or injury, causing pain and swelling.
Patellofemoral pain syndrome: This condition, also known as runner's knee, causes pain in the front of the knee, usually around or behind the patella. It's common in adolescents and young adults who are active in sports.

A. Malignancy: Although rare, malignancies such as osteosarcoma can present with bone pain and swelling. It's crucial to consider this possibility, especially if the pain is persistent, severe, or accompanied by other systemic symptoms like weight loss or fever.
Infection (e.g., osteomyelitis or septic arthritis): Infections can cause severe pain, swelling, and redness. These conditions are medical emergencies and require prompt diagnosis and treatment.
B. Avascular necrosis: This condition involves the death of bone tissue due to a lack of blood supply. It can occur in various bones, including those around the knee, and might present with pain.

D. Malingering: This refers to the intentional production of false or grossly exaggerated physical or psychological symptoms. It's unlikely in this scenario given the patient's consistent history and physical findings.
Bone cysts or tumors (benign or malignant): While the X-rays showed no evidence of tumors, rare conditions like unicameral bone cysts could potentially cause similar symptoms.
Chronic recurrent multifocal osteomyelitis (CRMO): A rare condition that can cause bone pain and swelling, often recurring over time. It's more common in children and adolescents.