title: How do i check if records of this id exists in another table
body: <p>I have these tables <img src="https://i.stack.imgur.com/tLg3V.jpg" alt="enter image description here"></p>
  
  <p>How do i check if a specific <code>ActivityTask</code> activityID and taskID have records in one of the tables  <code>threeHints</code> , <code>questions</code> and <code>questionhint</code>. No activityID and taskID can have records that exist in more than 1 table</p>
  
  <p>I am using entity framework and lambda expressions. I got stuck at how to write the codes to check for records existing in these 3 tables. </p>