JSFiddle - React, Tailwind, and code Playground

HTML

<div>
    <select id="currency" name="currency" onChange="display_payroll_div(this.selectedIndex);">
        <option value="0">Currency for your quote*</option>
        <option value="AUD">AUD</option>
        <option value="USD">USD</option>
        <option value="Pounds">GBP</option>
    </select>
</div>
<div id="payroll-div">
    <select id="report-payroll" name="report-payroll">
        <option value="0">Would you like us to do payroll?*</option>
        <option value="1">Yes, I would like payroll</option>
        <option value="2">No, I don't need payroll</option>
    </select>
</div>

JavaScript

function display_payroll_div(e){
    currency_value=document.getElementById('currency').value;
    document.getElementById('payroll-div').style.display = "none";
    if (currency_value == 'AUD') {
        document.getElementById('payroll-div').style.display = "block";
    }else{
    document.getElementById('report-payroll').value ='0';
    }
}