Which out of the following bones ossify first?
Mandible is the second bone, next to clavicle, to ossify in the body. 
It ossifies in membrane in its greater part. Each half of the body of mandible is ossified in membrane from 1 centre, which appears during 6th week I.U. near future mental foramen.
The parts ossifying in cartilage includes,
	
Incisive part, below the incisor teeth.
Upper half of ramus, above the level of mandibular foramen.
Condylar process.
Coronoid process.
Mandible
Nasal bone
Vomer
Occipital