change select_tag to select_tag"s"

app/views/admin/faqs/_form.html.erb

@@ -72,7 +72,7 @@
   <!-- Tag -->
   <div class="control-group">
     <label class="control-label muted">Tag</label>
-    <%= select_tag(f, @module_app) %>
+    <%= select_tags(f, @module_app) %>
   </div>
 
 </div>