David sustained a complete avulsion of his hamstring tendons from their origin on the ischial tuberosity. Hamstrings are part of what class of lever at the knee?
a) The hamstrings are part of a first-class lever, where the fulcrum is between the applied force and the load.
b) The hamstrings are part of a second-class lever, where the load is between the applied force and the fulcrum.
c) The hamstrings are not part of the lever system.
d) The hamstrings are part of a third-class lever, where the applied force is between the load and the fulcrum.