Final answer:
The iliac crest and the anterior superior iliac spine of the ilium are responsible for the prominent contoured appearance of the hips.
Step-by-step explanation:
the portion of ilium:
The portion of the ilium that causes the prominence of the hip is known as the iliac crest, particularly the anterior superior iliac spine, which is a notable bony landmark.
When hands are placed on the waist, the arching superior margin of the ilium can be felt along the waistline. This is the iliac crest, and at its front, the rounded protrusion known as the anterior superior iliac spine is a key bony landmark that can be felt at the anterolateral hip. Additionally, the muscles and ligaments that surround the iliac spines create attachment points which contribute to the hip's prominence. The prominence of the hip is visually apparent due to these structures and the fact that muscles and ligaments attach here, sometimes causing a dimple seen on the lower back at the posterior superior iliac spine location.