Final answer:
The posterior compartment of the leg incorporates muscles responsible for flexing the knee, extending the thigh, and plantar flexion of the foot.
Step-by-step explanation:
The common action of the muscles in the leg's posterior compartment is primarily facilitating movements like flexing the leg at the knee, extending the thigh, and assisting in the outward rotation of both the leg and thigh. Specifically, within the posterior compartment of the thigh, the hamstring group, which includes the biceps femoris, semitendinosus, and semimembranosus, is responsible for moving the back of the lower legs up and back toward the buttocks and for moving the thigh down and back.
In the posterior compartment of the lower leg, the deep muscles such as the gastrocnemius, soleus, and plantaris contribute to actions like plantar flexion, which lowers the sole to the ground, as seen in activities like foot-tapping or jumping.