Function f: X to itself omits b as an output (permissible as an injective function), but c has more than one input (cannot be injective). Cannot be surjective (but b is omitted). f is not a function—none.
Function g: the inputs and outputs form perfect pairs with nothing left out (the sets are the same size). Bijective.
Function h: R is omitted as an output and other mapping is unique—injective.