A neonate has a prominent defect at the base of this spine through which his meninges and spinal cord protrude. A failure of which the following processes is the most common cause of this type of defect?
选项：

A:Fusion of the vertebral arches;
B:Development of the body;
C:Development of the pedicle;
D:Development of primary vertebral ossification centers;
E:Development of the superior articular process