Post values in a Listbox without being selected

Is it possible to post the values of a Listbox without being selected?

My ListBox:

@Html.ListBoxFor(m => m.SelectedCatequistas, new MultiSelectList(ViewBag.SelectedCatequistas, "PessoaID", "Nome"), htmlAttributes: new
                           {
                               @class = "form-control",
                               Size = 15,
                               style = "width: 100%;"
                           })