Select

The native dropdown, styled — because native is the accessible one.

Department

Show the markup

<div class="cc-field">
  <label class="cc-label" for="ex-select">Department</label>
  <select class="cc-select" id="ex-select">
    <option>Town Clerk</option>
    <option>Assessor's Office</option>
    <option>Board of Health</option>
  </select>
</div>

Accessibility

A styled native <select> — screen reader, keyboard and mobile behavior come from the platform, where it's best.
For type-to-filter over long lists, use Suggestion.
Selecting an option must never itself trigger navigation (3.2.2) — pair with a Go button if it does.