Answer:
( C ) Cortical bone
Explanation:
The diaphyseal region of the bone , is the main or the medsection of the long bone.
The composition of Diaphyseal region is mainly of the cortical bone , bone marrow and the fat tissue i.e. the adipose tissue .
The middle tabular part of the diaphyseal region , composed of the compact bone is surrounded by the central marrow cavity which have the red or the yellow marrow.
Hence ,
The diaphyseal region is composed of cortical bone.
