**Core Concept**
The hip joint is a complex synovial joint stabilized by several ligaments, tendons, and muscles. The ligaments play a crucial role in limiting excessive movements and maintaining joint stability. In the context of hip joint extension, specific ligaments come into play to prevent overextension.

**Why the Correct Answer is Right**
The ligament that primarily limits extension at the hip joint is the **Iliofemoral ligament**. This ligament is a strong, Y-shaped ligament that connects the ilium to the femur. It is composed of dense, fibrous connective tissue and is one of the strongest ligaments in the body. During hip extension, the iliofemoral ligament tightens, preventing the femur from overextending beyond the horizontal plane.

**Why Each Wrong Option is Incorrect**
**Option A:** The **Pubofemoral ligament** primarily limits adduction and flexion at the hip joint, not extension.

**Option B:** The **Ischiofemoral ligament** is actually a weak ligament that provides some support to the hip joint, but it is not the primary ligament limiting extension.

**Option C:** The **Ligamentum teres** is a small, fibrocartilaginous ligament that connects the femoral head to the acetabulum. It is not involved in limiting extension at the hip joint.

**Clinical Pearl / High-Yield Fact**
In clinical practice, a patient with a torn iliofemoral ligament may present with a feeling of instability or a "giving way" sensation in the hip joint, particularly during heavy lifting or weight-bearing activities.

**Correct Answer: C. Ischiofemoral ligament is incorrect; the correct ligament is not listed among the options, but the correct answer is actually the Iliofemoral ligament.