title: What to return from non-async method with Task as the return type?
body: <p>Assume I have a method that is not async but returns a <code>Task</code> (because the definition is from an interface intended also for async implementations)</p>
  
  <pre><code>public Task DoWorkAsync(Guid id)
  {
       // do the work
  
       return ...;
  }
  </code></pre>
  
  <p>What is the best object to return? My current options:</p>
  
  <pre><code>return Task.Yield();
  return Task.FromResult&lt;object&gt;(null);
  
  // any of the other but cached in a static field and reused.
  </code></pre>