JSFiddle - React, Tailwind, and code Playground

HTML

<select id="selectA">
    <option value="0">Earth</option>
    <option value="1">Moon</option>
    <option value="2">Sun</option>
</select>

<input type="button" id="cmdA" onclick="javascript:fA()" value="Function A" />
<input type="button" id="cmdB" onclick="javascript:fB()" value="Function B" />

JavaScript

function fA() {
    var ddl = document.getElementById("selectA");
    if(ddl) {
        var text = ddl.options[ddl.selectedIndex].innerHTML;
        var value = ddl.options[ddl.selectedIndex].value;
        
        alert(value + " ---------- " + text);
    }
}

/*--------jQuery------------*/
function fB() {
    var ddl = $("#selectA option:selected");
    if(ddl) {
        var text = ddl.text();
        var value = ddl.val();
        alert(value + " ---------- " + text);
    }
   
}