Explanation

(d)
Conjugated proteins on hydrolysis give a non-protein portion is called prosthetic group.
[table] Protein | Prosthetic group ; Phosphoprotein | Lipid (e.g., lecithin) ; Glycoprotein | Sugar ; Chromoprotein | Colouring matter such as red coloured protophyrin [/table]
Since, all of them have non-protein part hence, all of them are conjugated protein.