JSFiddle - React, Tailwind, and code Playground

HTML

<select id="dateScope">
    <option value="">..select one option...</option>
    <option value="w">Weekly</option>
    <option value="m">Monthly</option>
    <option value="y">Yearly</option>
</select>
<div id="buttonsDiv"></div>

JavaScript

var days = ['Mon','Tues','Wed','Thu','Fri','Sat','Sun'];

function getContent(dateScope)
{
    var ret = "";
    switch(dateScope) {
        case "w": for(i in days)
            ret += "<button>"+days[i]+"</button>";
            break;
        case "m": for(i=1;i<=31;i++)
            ret += "<button>"+i+"</button>";
            break;
        case "y": for(i=1;i<=12;i++)
            ret += "<button>"+i+"</button>";
            break;
    }
    return ret;
}

$("#dateScope").change(function(){
    $("#buttonsDiv").html(getContent($(this).val()));
});