**Core Concept**
Posterior dislocation of the hip joint results in a characteristic attitude of the lower limb due to the disruption of the normal anatomical relationships between the femur and the acetabulum. The posterior wall of the acetabulum is compromised, leading to a change in the alignment of the femoral head and the acetabulum.

**Why the Correct Answer is Right**
In a posterior dislocation of the hip, the femoral head is displaced out of the acetabulum and posteriorly directed. This leads to a characteristic flexion, internal rotation, and adduction of the hip joint, resulting in the lower limb being positioned in a flexed, internally rotated, and adducted position. The sciatic nerve, which runs posteriorly to the hip joint, is also stretched or compressed, leading to pain and sensory changes in the affected limb.

**Why Each Wrong Option is Incorrect**
**Option A:** This option is incorrect as it does not accurately describe the typical attitude of the lower limb in a posterior dislocation of the hip.
**Option B:** This option is incorrect as it describes a different type of hip dislocation, where the femoral head is displaced anteriorly.
**Option C:** This option is incorrect as it describes a different type of hip deformity, where the femur is shortened and the hip is dislocated.

**Clinical Pearl / High-Yield Fact**
In a posterior dislocation of the hip, the affected limb is often shortened and externally rotated, but in reality, the limb is flexed, internally rotated, and adducted. This is a classic exam trap, and students should remember this characteristic attitude of the lower limb to accurately diagnose posterior dislocation of the hip.

**Correct Answer: D.**