Different water samples A, B, C and D have 150 ppm each of CaCl2,MgSO4,CaSO4 and MgCl2 respectively. The order of degree of hardness of these samples is
Four different water samples A, B, C and D each contains150 ppm of CaCl2, MgSO4,CaSO4, and MgCl2 respectively.Choose the correct order of degree of hardness of these samples.