**Core Concept**
Posterior dislocation of the hip occurs when the femoral head is displaced posteriorly relative to the acetabulum, often resulting from a significant force applied to the knee while the hip is flexed and the foot is fixed. This can be seen in high-energy trauma, such as motor vehicle accidents. The femoral head dislocates out of the acetabulum and may be driven posteriorly by the surrounding soft tissues.

**Why the Correct Answer is Right**
In a posterior dislocation of the hip, the patient's hip will typically be in a flexed, internally rotated, and adducted position. This is due to the short external rotators and adductors of the hip, which contract and pull the femur posteriorly and medially. The hip's flexion is also a result of the iliopsoas muscle, which contracts to maintain the flexed position of the hip. The patient's pain and discomfort will be significant, and they may be unable to bear weight on the affected limb.

**Why Each Wrong Option is Incorrect**
**Option A:** This option is incorrect as it does not accurately describe the position of the hip in a posterior dislocation. The hip is typically flexed, not extended.
**Option B:** This option is incorrect as it does not accurately describe the internal rotation of the hip in a posterior dislocation. The hip is typically internally rotated, not externally rotated.
**Option C:** This option is incorrect as it does not accurately describe the adduction of the hip in a posterior dislocation. The hip is typically adducted, not abducted.

**Clinical Pearl / High-Yield Fact**
In a patient with posterior dislocation of the hip, it is essential to immobilize the affected limb in a flexed, internally rotated, and adducted position to prevent further injury and facilitate reduction.

**Correct Answer:** C.