Final answer:
The ilium, ischium, and pubis bones of the os coxae fuse at the acetabulum. This cavity is where these three hip bones converge and where the femur fits to form the hip joint. The superior part of the hip bone is formed by the ilium.
Step-by-step explanation:
The three bones of the os coxae, namely the ilium, ischium, and pubis, fuse at the acetabulum. The acetabulum is a deep, cup-shaped cavity located on the lateral side of the hip bone and is a part of the hip joint. It accommodates the head of the femur, forming the hip joint. Despite the pubic symphysis being a joint where the pubic portions meet anteriorly, and the sacroiliac joint being where the ilium connects to the sacrum, it is the acetabulum where all three hip bones actually converge and fuse.
Which component forms the superior part of the hip bone? The answer is a. ilium, which is the fan-like, superior region forming the largest part of the hip bone and securely united to the sacrum at the sacroiliac joint.