select list because it is not contained in either an aggregate function or the GROUP BY clause.

I wrote sp like below,

Alter procedure First_Proc
  (@fromdate datetime,
  @todate datetime
  )
  as
  begin
  select DATEPART(YY,ModifiedDate) as Year
        ,DATEPART(QQ,ModifiedDate) as Quarter
        ,DATEPART(MM,ModifiedDate) as Month
        ,Name
        ,rowguid              
   from [AdventureWorks2012].[Production].[ProductModel]
  where ModifiedDate between (@fromdate) and (@todate)
  group by DATEPART(YY,ModifiedDate),DATEPART(QQ,ModifiedDate),DATEPART(MM,ModifiedDate)
  order by DATEPART(YY,ModifiedDate),DATEPART(QQ,ModifiedDate),DATEPART(MM,ModifiedDate)
  end

But am getting following Error...

Column 'AdventureWorks2012.Production.ProductModel.rowguid' is invalid in the select list because it is not contained in either an aggregate function or the GROUP BY clause.