def validateOptions(args):
    """Validates arguments for options that take arguments, and also checks for
    options that are mutually exclusive."""
    if args.hex:
        if args.output_radix != 10 and args.output_radix != 16:
            return False, "-r and -x can't be used together"
        if args.octal:
            return False, "-x and -o can't be used together"
    if args.octal:
        if args.output_radix != 10 and args.output_radix != 8:
            return False, "-r and -o can't be used together"
    if args.comma and args.integer_grouping > 0:
        return False, "rpn:  -c can't be used with -i"
    return True, ''
