What is the correct template syntax for using the built-in ngFor structural directive to render out a list of productNames?
<ul> <li ngFor="let productName of productNames">{{ productName }}</li> </ul>
<ul> <li [ngFor]="let productName of productNames">{{ productName }}</li> </ul>
<ul> <li *ngFor="let productName of productNames">{{ productName }}</li> </ul>
<ul> <? for productName in productNames { ?> <li>{{ productName }}</li> <? } ?> </ul>
Angular.io- Structural Directives