I have a Lv 30 cubone with ability lighting rod. When I saw at which Lv cubone evolves, also saw that its ability Rock Head changes to Cursed Body whereas its other ability ie lighting rod remains as it is. Is there any chance for lighting rod change to Cursed Body when it evoves?
No, your A-Marowak will not get Cursed Body.
At least, not on it's own. You will need to use an Ability Capsule to switch the Ability, either as a Cubone or as an A-Marowak.