This is a real-world medical entrance exam question, please give the true answer based on the question and selection. Topic name: None, Subject name: Surgery
A 24 years old college student while playing hockey injured his right knee. This patient presents after 3 months with instability of knee joint in it full extension without instability at 90 degree of flexion. The structure most commonly damaged is: 
Select and explain. 
A. Posterolatilal pa of anterior cruciate ligament, B. Anteromedial pa of anterior cruciate ligament, C. Posterior cruciate ligament, D. Anterior hom of medial meniscus
A: Posterolatilal pa of anterior cruciate ligament
Answer: A: Posterolatilal pa of anterior cruciate ligament 
Explanation: Ans. a. Posterolateral pa of anterior cruciate ligament