Final answer:
The kneecap is correctly identified as the patella, a triangular sesamoid bone that lies in the tendon of the quadriceps femoris muscle and articulates with the femur to assist in knee movement. The correct option is b).
Step-by-step explanation:
The part of the body often called the kneecap is the patella. The patella is a triangular bone that sits anterior to the knee joint and is embedded in the tendon of the femoral extensors, known as the quadriceps. It is a sesamoid bone, meaning it is incorporated into the tendon of a muscle where that tendon crosses a joint.
The patella articulates with the patellar surface of the femur, providing a protective function and increasing the leverage power of the quadriceps femoris muscle as it acts across the knee.
The patella also functions to reduce friction, improving knee extension. This bone does not articulate with the tibia but is crucial for the proper functioning of the knee joint.
Considering the options provided: a) Pelvis b) Patella c) Coccyx d) Tibia, the correct answer is b) Patella.