A 32-year-old mother from a poor rural county gives birth to a male child. Based on her circumstances, she sought almost no prenatal care, visiting a physician only once when she first thought she was pregnant. This child is born with a catastrophic developmental defect associated with a failure of the anterior neuropore to close. Which of the following most specifically designates this developmental failure? (A) Anencephaly (B) Dermal sinus (C) Encephalocele (D) Meningocele (E) Meningomyelocele