DB Design :: Creating Appropriate Index For Table?

I have a table called as  A table :

CREATE TABLE [dbo].[A](
 [AutoID] [int] IDENTITY(1,1) NOT NULL,
 [ProID] [int] NOT NULL,
 [LID] [varchar](12) NOT NULL,
 [EventID] [varchar](12) NOT NULL,
 [HEventID] [varchar](12) NULL, 
) ON [PRIMARY]   

How I should creating the appropiate index for this table?A few option that I think ok.

Opt 1 : creating a primary key on the autoID with create index . create non clustered index on ProID and EventID
Opt 2 : create a primary key on the autoID with non clustered index . create clustred index on ProID and EventID .
opt 3: create primary key on the ProID and EventID with clustered index.

I have read thru the article on the primary key, clustered and non clustered indexing. However when I want to applyied the indexing..I feel a bit lost.But among the 3 option.... what is the different..