This is a real-world medical entrance exam question, please give the true answer based on the question and selection. Topic name: Urethra & Penis, Subject name: Surgery
[{'content': 'A 20-years old male presents with scrotal mass. The first investigation to be done is: \nSelect and explain. \nA. Clinical evaluation (Palpation and transillumination), B. USG, C. Biopsy, D. AFP', 'role': 'user'}, {'content': 'Answer: A \nExplanation: Ans. (a) Clinical evaluation (palpation and transillumination)* Best Investigation is USG* The question asks the first investigation - Clinical examination may show nodules and loss of testicular sensation and secondary hydrocele.', 'role': 'assistant'}]