JSFiddle - React, Tailwind, and code Playground

HTML

<select id="slt">
</select>

JavaScript

var json = [{"JD_No":1,"JD_Name":"Network Administrator"}, {"JD_No":2,"JD_Name":"System Administrator"}];

var options = [], key, value;

$.each(json, function() {
    $.each(this, function(k, v) {
        console.log(k);
        if(typeof v === 'number') {
            key = v;
        }
        else {
            value = v;
        }
    });
    options.push({'key': key, 'value': value});
});

console.log(options);


$.each(options, function() {
    var option = $('<option>').attr('value', this.key).html(this.value);
    
    $('#slt').append(option);
});