The majority of spinal hernias occur in the lumbar region due to:

The majority of spinal hernias occur in the lumbar region largely due to the natural curvature of the spine. The lumbar region is designed with a lordotic curvature, which allows for the distribution of weight and stress during various activities. However, this curvature also means that the lumbar discs are subject to significant pressure, especially when bending or lifting improperly.

The anatomical structure of the lumbar region, coupled with the mechanical load placed upon it during daily activities, increases the likelihood of disc degeneration and herniation in this area. As the lumbar spine supports most of the body's weight and is involved in numerous movements, it experiences more strain than other regions of the spine, making it more susceptible to injury and herniation.

In contrast, good lifting techniques and managing the load effectively can mitigate the risk of hernias, so the options suggesting employing proper techniques or marking a lack of age-related changes are not the primary reasons for the occurrence of hernias. The mention of increased activity could also relate to injury but does not directly link to the inherent structural reasons that predispose the lumbar region to hernias.