The correct answer is B. Humerus. The humerus is the bone in the upper arm, while the tibia, fibula, and femur are all bones in the leg.
The humerus is the longest bone in the upper arm. It connects the shoulder to the elbow. The humerus is a long, slender bone with a rounded head at one end and a knobby end at the other. The head of the humerus fits into the socket of the shoulder blade, forming the shoulder joint. The knobby end of the humerus fits into the ulna and radius, forming the elbow joint.
The tibia is the larger of the two bones in the lower leg. It runs from the knee to the ankle. The tibia is a long, slender bone with a rounded end at the knee and a flat end at the ankle. The rounded end of the tibia fits into the femur, forming the knee joint. The flat end of the tibia fits into the talus, forming the ankle joint.
The fibula is the smaller of the two bones in the lower leg. It runs parallel to the tibia from the knee to the ankle. The fibula is a long, slender bone with a pointed end at the knee and a flat end at the ankle. The pointed end of the fibula fits into the tibia, forming the knee joint. The flat end of the fibula fits into the talus, forming the ankle joint.
The femur is the longest and strongest bone in the body. It runs from the hip to the knee. The femur is a long, slender bone with a rounded head at one end and a knobby end at the other. The head of the femur fits into the socket of the pelvis, forming the hip joint. The knobby end of the femur fits into the tibia and patella, forming the knee joint.