Cation exchanger used to remove permanent hardness uses :
Granular insoluble organic acid resin
Granular soluble organic acid resin
Granular insoluble inorganic acid resin
Granular soluble organic acid resin
Cationic exchanger resin has granular insoluble organic acids with long hydrocarbon chains and is attached with groups at one end.
Therefore, option(1) is correct.