Which muscle extends the knee and is part of the quadriceps group?

Which muscle extends the knee and is part of the quadriceps group?

• A. Vastus Medialis
• B. Vastus Lateralis
• C. Tibialis Anterior
• D. Gastrocnemius

Answer: (A)

Knee extension is produced by the quadriceps femoris group, a set of muscles on the front of the thigh. This group includes four muscles: rectus femoris, vastus medialis, vastus lateralis, and vastus intermedius. All of them contribute to straightening the knee when they contract. Among the options, the muscle that is a true part of the quadriceps and extends the knee is vastus medialis. The tibialis anterior moves the foot (dorsiflexion), not the knee. The gastrocnemius crosses the knee but mainly plantarflexes the ankle and is not part of the quadriceps, so it isn’t the knee-extending quadriceps muscle.

Knee extension is produced by the quadriceps femoris group, a set of muscles on the front of the thigh. This group includes four muscles: rectus femoris, vastus medialis, vastus lateralis, and vastus intermedius. All of them contribute to straightening the knee when they contract. Among the options, the muscle that is a true part of the quadriceps and extends the knee is vastus medialis. The tibialis anterior moves the foot (dorsiflexion), not the knee. The gastrocnemius crosses the knee but mainly plantarflexes the ankle and is not part of the quadriceps, so it isn’t the knee-extending quadriceps muscle.