title: iterating through the hierarchy of objects - C# - linq
body: <p>I have an object (say A) with hierarchy as below,</p>
  
  <blockquote>
    <p>obj A --> Contains list of obj B --> Contains list of obj C -->
    Contains list of obj D</p>
  </blockquote>
  
  <p>Given the obj A, i need to get the list of all obj D in total, irrespective of its association with obj C and obj B. something like <code>List&lt;D&gt; GetAllofD(A a)</code></p>
  
  <p>Can you please suggest me the best way to get it done - don't want to use multiple <code>for loops</code>. Any better approach using linq?</p>