**Core Concept**
The **endodermal cloaca** is a shared precursor to several structures in the pelvis, including parts of the urinary, reproductive, and digestive systems. It is formed during embryonic development and eventually differentiates into distinct components. Understanding the derivation of these structures is crucial for comprehending various congenital anomalies and surgical approaches.

**Why the Correct Answer is Right**
The correct answer is related to the structures that do not develop from the **endodermal cloaca**. The **endodermal cloaca** gives rise to the bladder, urethra, and parts of the reproductive system, as well as the rectum. However, some surrounding muscles and supportive structures have different origins.

**Why Each Wrong Option is Incorrect**
**Option A:** This choice is incorrect because it likely refers to a structure that indeed develops from the **endodermal cloaca**.
**Option B:** Similarly, this option is incorrect as it probably pertains to another derivative of the **endodermal cloaca**.
**Option C:** This choice is also incorrect for the same reason, being a structure that originates from the **endodermal cloaca**.

**Clinical Pearl / High-Yield Fact**
A key point to remember is that the **endodermal cloaca** gives rise to several critical pelvic structures, and understanding its development can help in diagnosing and managing congenital anomalies. Recognizing the origins of different structures can also guide surgical planning.

**Correct Answer:** D. External genitalia and perineal muscles do not develop from endodermal cloaca, they originate from ectoderm and mesoderm respectively.