Final answer:
The attachment site for the hamstrings, adductor magnus, and sacrotuberous ligament is the ischial tuberosity of the hip bone.
Step-by-step explanation:
The attachment site for the hamstrings, adductor magnus, and sacrotuberous ligament is the ischial tuberosity of the hip bone, also known as the sit bone. The ischial tuberosity is a bony prominence located at the bottom of the pelvis, and it provides a point of attachment for various muscles and ligaments in the hip and thigh region.