One of the Most Common Knee Injuries Is the Tearing

One of the most common knee injuries is the tearing of the anterior cruciate ligament (ACL) . How would an injury like this affect the function of the knee?

A) Ligaments attach muscle to bone, so tearing of the ligament would mean that the knee muscles would no longer be able to cause the joint to bend.
B) Ligaments lubricate the cartilage in a joint, and tearing the ligament would let the lubricant leak out. This would cause bones in the knee to grind against each other, making it painful to bend the knee.
C) Ligaments hold the bones of the knee in the proper orientation. Tearing the ligament could disrupt the alignment of the knee, making the knee difficult to bend.
D) Ligaments are the muscles that surround a joint. Muscle tears can be painful, but they heal quickly and they usually do not affect knee function.