Final answer:
An Ehmer sling is used to support and protect the hip joint after an injury, and the ilium is the superior part of the hip bone.
So option (D) is correct.
Step-by-step explanation:
The correct answer to the question, "A(n) ________ is a non-weight-bearing sling applied to the pelvic limb to protect the hip joint after injury," is d) Ehmer sling. An Ehmer sling is used to protect the hip joint by holding the hind limb in a flexed position and externally rotating it. This type of sling is commonly used following reductions of hip luxations to maintain joint stability.
As for the question's additional part regarding which component forms the superior part of the hip bone, the correct answer is a) ilium. The ilium is the large, fan-shaped part of the hip bone that forms the uppermost portion, commonly referred to as the 'wing' of the hip bone, and it plays a crucial role in weight-bearing and muscle attachment.