Which muscles contribute to trunk rotation and lateral bending?

The answer is appropriate because the psoas major, quadratus lumborum, and external oblique are indeed significant contributors to trunk rotation and lateral bending.

The psoas major, although primarily known for its role in hip flexion, also assists in stabilizing the lumbar spine and can contribute to lateral bending. The quadratus lumborum plays a crucial role in lateral flexion of the trunk and helps stabilize the pelvis. Finally, the external oblique is directly involved in trunk rotation and lateral bending, allowing the torso to twist and bend sideways effectively.

Together, these muscles coordinate to enable dynamic movements of the trunk, facilitating actions such as twisting and bending, which are important in various functional activities and athletic movements.