<prompt> The main action of muscle obturator externus muscle is?Medial rotation of thighLateral rotation of thighFlexion of thighExtension of thigh  <response>: Obturator externus muscle attaches to the external surface of the obturator membrane, adjacent bone, and trochanteric fossa. The obturator externus muscle laterally rotates the femur at the hip joint. The obturator nerve L3 and L4 innervates this muscle. 