JSFiddle - React, Tailwind, and code Playground

HTML

<select size="1" name="usgsfeed" id="usgsfeed" onchange="usgsChanged(this);">
<option value="usgs_hour">Past hour, all earthquakes</option>
<option value="usgs_day" SELECTED>Past day, magnitude > 1</option>
<option value="usgs_week">Past week, magnitude > 2.5</option>
<option value="usgs_month">Past month, magnitude > 2.5</option>
<option value="none">None</option>
</select>

JavaScript

function usgsChanged(el) {
    window["display_" + el.options[el.selectedIndex].value]();
}

function display_usgs_hour() {
    alert("display_usgs_hour");
}

function display_usgs_day() {
    alert("display_usgs_day");
}
    
function display_usgs_week() {
    alert("display_usgs_week");
}
    
function display_usgs_month() {
    alert("display_usgs_month");
}
    
function display_none() {
    alert("display_none");
}