Study the following and pick up the correct statements
I. Intercalated discs are peculiar to skeletal muscles
II. In nervous tissue only ependymal cells develop from mesoderm
III. Neutrophils are commonly called microscopic police men
IV. Most of the cranial bones are dermal bones

Inter calated discs are present in cardiac muscles.Mesoglia cells  are mesodermal in origin not ependyma. Neutrophils are phagocytes,protect the body from  invading foreign molecules and organisms, hence called microscopic police men. Cranial bones are formed by the ossification of mesenchyme ,hence called dermal bones.