Where does the external abdominal oblique muscle insert?

The external abdominal oblique muscle inserts at the linea alba, which is a fibrous structure that runs down the midline of the abdomen. This muscle plays a crucial role in flexing and rotating the trunk, as well as stabilizing the torso during movement. By inserting at the linea alba, the external abdominal oblique can effectively contribute to trunk movements and maintain abdominal tension, which is vital for posture and core stability. The other options, while related to abdominal and lumbar anatomy, do not represent the correct insertion point for this muscle.