What is the best way to do this in Delphi?

I need to create a adoquery in execution time.

what is the best way to create, with application or nil in create?

var
  TQ : Tadoquery;
begin
  TQ := Tadoquery.create(Application)

  OR

  TQ := Tadoquery.create(Nil)
end;



End to destoy it?

TQ.Close;
FreeAndNil(TQ)

Or

TQ.free


Thanks