Which condition is characterized by a failure of vertebral arches to close during fetal development?

The condition characterized by a failure of the vertebral arches to close during fetal development is indeed spina bifida. This neural tube defect occurs when the spine and surrounding structures do not fully form, leading to potential physical and neurological impairment. During the early stages of pregnancy, the neural tube, which will become the spinal cord and surrounding vertebrae, should close properly to ensure normal spinal development. When this closure does not occur, it can result in various forms of spina bifida, ranging in severity from hidden forms that may cause no symptoms to more severe cases that present significant physical challenges and require medical intervention.

In contrast, cerebral palsy, dyscalculia, and dyspraxia involve different types of developmental issues. Cerebral palsy primarily affects motor function due to damage to the brain, often related to complications at birth or shortly thereafter. Dyscalculia refers to a specific learning disability that affects an individual's ability to understand and work with numbers, while dyspraxia affects motor skill development and coordination but doesn't involve vertebral development. Therefore, spina bifida is the only condition listed that directly relates to the failure of vertebral arch closure during fetal development.