A healthy 6-month-old child si brought to the emergency room with history of sudden onset of seizures. The seizures are characterized by sudden flexions of neck and trunk, and extensions of both upper and lower extremities. He was born by normal spontaneous vaginal delivery with good Apgar scores. On second day of life, he was discharged. Mother denies history of trauma. Physical examination reveals normal vital signs and neurological findings. Head CT scan is normal. The most likely diagnosis is:
a. Meningitis
b. Child abuse X Infantile spasms
c. Normal newborn movements
d. Immunization induced seizures