Sometimes back, when I was working on TurboScrum project with angular and bootstrap, I bumped into this issue. I was unable to get the bootstrap drop down working. After couple of hours of hard research I found the solution was rather too simple.

What I had is,

<script type="text/javascript" src="Scripts/bootstrap.min.js"></script>
<script type="text/javascript" src="Scripts/jquery-2.1.1.min.js"></script>

instead of,

<script type="text/javascript" src="Scripts/jquery-2.1.1.min.js"></script>
<script type="text/javascript" src="Scripts/bootstrap.min.js"></script>

"The jQuery should be included before bootstrap. The order matters(ofcourse)"