Consider the following database table having A, B, C and D as its four attributes and four possible candidate keys (I, II, III and IV) for this table:
If different symbols stand for different values in the table (e.g. d1d1 is definitely not equal to d2d2) then which of hte above could not be the candidate key for the database table?
- I nad III only
- III and IV only
- II only
- I only