Select option(выбрать опцию)

function chooseLanJs() { 
  var select = document.getElementById('slct');  
  var selectedValue = select.options[select.selectedIndex].value; 
    if (selectedValue == 2) { 
    } 
    else { 
    } 
} 
chooseLanJs(); 
 
 
function openMnuJs() { 
    document.getElementById("myDropdown").classList.toggle("show"); 
} 
 
window.onclick = function(event) { 
  if (!event.target.matches('#dropbtn')) { 
 
    var dropdowns = document.getElementsByClassName("dropdown-content"); 
    var i; 
    for (i = 0; i < dropdowns.length; i++) { 
      var openDropdown = dropdowns[i]; 
      if (openDropdown.classList.contains('show')) { 
        openDropdown.classList.remove('show'); 
      } 
    } 
  } 
}

.dropdown-content { 
    position: absolute; 
    background-color: white; 
    z-index: 9000; 
    -webkit-border-radius: 4px; 
-moz-border-radius: 4px; 
border-radius: 4px; 
width: 20%; 
height: 170px; 
text-align: left; 
display: none; 
} 
.show {display:block;}

<button onclick="openMnuJs()" id="dropbtn"><span id="txt-mnu">JavaScript</span></button> 
		  			  <div id="myDropdown" class="dropdown-content"> 
		  			  	<div class="language"> 
		  				<span>Язык</span> 
  <div class="select" onchange="chooseLanJs()"> 
    <select name="slct" id="slct"> 
      <option value="1">JavaScript</option> 
      <option value="2">CoffeeScript</option> 
      <option value="3">No JS</option> 
      <option value="4">Nice!</option> 
    </select> 
  </div> 
</div> 
</div>