A 36-year-old man presents to you complaining of right scrotal swelling. He states that the swelling has been present for 1 week. He initially noticed the swelling sholy after moving furniture for his new living room. He denies any nausea, vomiting, change in bowel habits, abdominal pain, or urinary tract symptoms. He has no other significant medical or surgical history. On examination, he has an enlarged right hemi-scrotum with a mass that appears to be originating at the level of the external inguinal ring. With the patient completely relaxed, the physician is able to reduce the mass by pushing it back through the external inguinal ring. With the mass reduced, the physician instructs the patient to perform a Valsalva maneuver, upon which a protrusion is felt at the external inguinal ring. Once the mass is reduced, the testicle appears normal in size and consistency. Which of the following is the most likely diagnosis?