At birth, mental foramen opens:: (A) Below sockets of deciduous canines, (B) In front of socket of deciduous canine, (C) Below sockets of deciduous molars, (D) Behind sockets of deciduous molars
Answer is C. Key concept:
At birth the mental foramen, opens below the sockets for the two deciduous molar teeth near the lower border.
This is so because the bone is made up only of the alveolar part with teeth sockets. The mandibular  canal runs near the lower border. The foramen and canal gradually shift upwards.