Which two actions should you perform?

You are implementing a new method named ProcessData. The ProcessData() method calls a third-party component that performs a long-running operation to retrieve stock information from a web service.
The third-party component uses the IAsyncResult pattern to signal completion of the long- running operation so that the UI can be updated with the new values.
You need to ensure that the calling code handles the long-running operation as a System.Threading.Tasks.Task object to avoid blocking the UI thread. Which two actions should you perform? (Each correct answer presents part of the solution. Choose two.)
A. Create a TaskCompletionSource<T> object.
B. Call the component by using the TaskFactory.FromAsync() method.
C. Apply the following attribute to the ProcessData() method signature: [Methodlmpl(MethodlmplOptions.Synchronized)]
D. Apply the async modifier to the ProcessData() method signature.