The bone of which organ is the longest in the human body?

The correct answer is: The thigh bone (femur).

The thigh bone is the longest bone in the human body. It is located in the upper leg and connects the hip to the knee. The femur is a long, strong bone that supports the weight of the body and allows for movement of the leg.

The spinal cord is a long, thin bundle of nerves that runs from the brain down the back. It is not a bone.

The rib cage is a series of bones that protect the lungs and heart. It is not a single bone.

The ankle bone is a small bone that connects the foot to the leg. It is not the longest bone in the human body.