Which condition is characterized by painful, tender, and swollen testis?

Orchitis is the correct answer because it specifically refers to the inflammation of the testis, which often results in painful, tender, and swollen testes. This condition can be caused by infections, including viral (such as mumps) or bacterial infections, and is distinct in its presentation of acute pain and swelling, which are hallmark symptoms that differentiate it from other conditions affecting the genitourinary system.

In contrast, hydrocele involves the accumulation of fluid around the testicle, leading to swelling but typically does not cause pain or tenderness. Prostatitis relates to inflammation of the prostate gland and may present with pelvic pain, urinary symptoms, or fever, but it does not directly affect the testis. Prostate cancer often does not present with acute swelling or tenderness of the testis, and symptoms can be more insidious, manifesting as urinary issues or systemic symptoms rather than localized pain and swelling. Thus, the specific symptoms of orchitis make it the condition that aligns with the description in the question.