**Core Concept**
Genital tuberculosis is a form of extrapulmonary tuberculosis that affects the genital organs, primarily the fallopian tubes, uterus, and ovaries in females, and the epididymis, testes, and seminal vesicles in males. It is a complication of pulmonary tuberculosis and is usually acquired through hematogenous spread.

**Why the Correct Answer is Right**
The correct answer is **C. Fallopian tubes**. The fallopian tubes are the most common site of genital tuberculosis in females, accounting for approximately 90% of cases. This is due to the high vascularity and rich lymphatic supply of the fallopian tubes, which facilitates the spread of Mycobacterium tuberculosis from the lungs to the genital organs. The bacteria infect the mucosal lining of the fallopian tubes, leading to inflammation, scarring, and eventual tubal occlusion.

**Why Each Wrong Option is Incorrect**
* **Option A:** While the uterus can be involved in genital tuberculosis, it is not the most common site. Uterine tuberculosis is often associated with tubal involvement.
* **Option B:** Ovarian involvement in genital tuberculosis is rare and usually occurs in conjunction with tubal or uterine involvement.
* **Option D:** Testicular involvement in genital tuberculosis is rare and typically occurs in males with a history of pulmonary tuberculosis.

**Clinical Pearl / High-Yield Fact**
It is essential to consider genital tuberculosis in the differential diagnosis of infertility, recurrent miscarriage, and pelvic pain in females, especially in regions with a high prevalence of tuberculosis. A high index of suspicion and appropriate diagnostic tests, such as endometrial biopsy and laparoscopy, can lead to early diagnosis and treatment.

**Correct Answer:** C. Fallopian tubes