**Core Concept**
The deep perineal pouch is a fascial compartment in the perineum that contains vital structures for urinary and reproductive functions. It is bounded by the inferior fascia of the urogenital diaphragm and the superior fascia of the urogenital diaphragm.

**Why the Correct Answer is Right**
The deep perineal pouch contains the external urethral sphincter, the deep transverse perineal muscles, and the bulb of the vestibular glands in females. These structures are critical for maintaining urinary continence and supporting the pelvic organs. The external urethral sphincter is a skeletal muscle that surrounds the urethra and plays a key role in voluntary urination.

**Why Each Wrong Option is Incorrect**
**Option A:** The contents of the deep perineal pouch include the external urethral sphincter, which plays a crucial role in maintaining urinary continence. Therefore, option A is a content of the deep perineal pouch.
**Option B:** The deep perineal pouch does not contain the superficial perineal pouch, which is a separate fascial compartment located superficial to the urogenital diaphragm. Therefore, option B is incorrect.
**Option C:** The deep perineal pouch contains the bulb of the vestibular glands in females, which are essential for vaginal lubrication and fertility. Therefore, option C is a content of the deep perineal pouch.
**Option D:** The deep perineal pouch does not contain the ischiocavernosus muscles, which are located in the superficial perineal pouch. Therefore, option D is incorrect.

**Clinical Pearl / High-Yield Fact**
The perineal fascia is a vital structure that separates the deep perineal pouch from the superficial perineal pouch. Understanding the anatomy of the perineal fascia is crucial for diagnosing and treating perineal injuries and infections.

**Correct Answer:** B. The superficial perineal pouch is a separate fascial compartment located superficial to the urogenital diaphragm.