JSFiddle - React, Tailwind, and code Playground

HTML

<script src="https://code.jquery.com/jquery-2.1.4.min.js"></script>
<script src="https://maxcdn.bootstrapcdn.com/bootstrap/3.3.5/js/bootstrap.min.js"></script>
<link rel="stylesheet" href="https://maxcdn.bootstrapcdn.com/bootstrap/3.3.5/css/bootstrap.min.css">
<div id="option-selection">
     <h3>Select an Option</h3>

    <div class="dropdown">
        <button class="btn btn-primary dropdown-toggle" type="button" data-toggle="dropdown">Available Options&nbsp&nbsp<span class="caret"></span>

        </button>
        <ul class="dropdown-menu">
            <li><a href="#">Option</a>

            </li>
            <li><a href="#">Option</a>

            </li>
            <li><a href="#">Option</a>

            </li>
            <li><a href="#">Option</a>

            </li>
            <li><a href="#">Option</a>

            </li>
            <li><a href="#">Option</a>

            </li>
            <li><a href="#">Option</a>

            </li>
            <li><a href="#">Option</a>

            </li>
            <li><a href="#">Option</a>

            </li>
            <li><a href="#">Option</a>

            </li>
        </ul>
    </div>
    <!--dropdown-->
</div>
<!--option selection-->

CSS

#option-selection {
    text-align: center;
    padding-top: 5px;
    padding-bottom: 25px;
    border-top: 1px solid black;
    border-bottom: 1px solid black;
}

.open>.dropdown-menu {
    width: 160px;
    left: 50%;
    margin-left: -80px;
}