Derived class syntax

1 derived_class :
2+ ,
2.0? 
2.0 virtual
2.0.1? 
2.0.1 public
2.0.1 private
2.0.1 protected
2.0.0 public
2.0.0 private
2.0.0 protected
2.0.1? virtual
2.1 qualified_class_specifier