Which muscle group is primarily responsible for extending the knee joint?

• A. Quadriceps femoris
• B. Tibialis anterior
• C. Gastrocnemius
• D. Hamstrings

Answer: (A)

Verified step by step guidance

1. Step 1: Understand the anatomy of the knee joint and the muscles involved in its movement. The knee joint primarily allows flexion (bending) and extension (straightening).
2. Step 2: Identify the muscle groups listed in the problem: Quadriceps femoris, Tibialis anterior, Gastrocnemius, and Hamstrings. Consider their anatomical locations and primary functions.
3. Step 3: Recall that the Quadriceps femoris is a group of muscles located at the front of the thigh, and its main function is to extend the knee joint.
4. Step 4: Recognize that the Hamstrings, located at the back of the thigh, primarily function to flex the knee, not extend it.
5. Step 5: Note that the Tibialis anterior is involved in dorsiflexion of the foot, and the Gastrocnemius assists in plantarflexion of the foot and also helps flex the knee, but is not the primary extensor.