ans
1) I need provide the orginal passport copy of my parents to ICA?
No need. But just the photocopy with first and last 3 pages
2) Should I apply visa; visa&visit pass; entry visa?
Entry visa only. They will issue you a visit pass oncee you arrice in SP.
3) Do i need mail phots of my parents from china?
Can get softcopies n print out here. Anyway, you need both soft and hard copies. The former is for SAVE submission and later for collection afterwards