Multiple choice Hexagonal crystal system is present in Graphite, ZnO and CdS NaCl, HgS and Graphite KNO3, BaSO4 and CaCO3 ZnO, HgS and CdS CdS, NaCl and Graphite Reveal answer Fill a bubble to check yourself A Correct answer Explanation Hexagonal crystal system is present in Graphite, ZnO and CdS.