Which code should you use?

You are creating a Web service.
You need to add an operation that can be called without returning a message to the caller.
Which code should you use?

A.
[WebMethod]
[SoapDocumentMethod(OneWay = true)]
public bool ProcessName(string name)
{
…
return false;
}

B.
[WebMethod]
[OneWay()]
public void ProcessName(string name)
{
…
}

C.
[WebMethod]
[SoapDocumentMethod(OneWay = true)]
public void ProcessName(string name)
{
…
}

D.
[WebMethod]
[SoapDocumentMethod(Action = "OneWay")]
public void ProcessName(string name)
{
…
}