Hi! I have a question. I need to list the children with the "Active == true" property from a custom controller and from the .cshtml

Controller

public class PollsController : SurfaceController
{
    private List<Theme> ThemeList()
    {
        var themePageList = Umbraco.Content(CurrentPage.Id).Children.Where("¿¿¿???");
        var themeList = new List<Theme>();

        foreach (var currentTheme in themePageList)
        {
            themeList.Add(
                new Theme
                {
                    ID = currentTheme.Id,
                    Title = currentTheme.Name,
                }
                );
        }

        return themeList;
    }
}

public ActionResult RenderPoll()
{

var viewModel = new PollViewModel
{
    Themes = ThemeList()
};

return PartialView("~/Views/Partials/_Polls.cshtml", viewModel);

}

And if to not filter on the controller, as I do to filter the view?

CSHTML

@model Encuestas.ViewModels.PollViewModel

@foreach (var currentTheme in Model.Themes.Where("¿¿¿???")
{
    <div>
        <p>
            <h1 style="text-align: center">@currentTheme.Title</h1>
        </p>
    </div>
}

Umbraco content

Polls
    Theme 1
        Question 1
            Answer 1
            Answer 2
            Answer 3
            Answer 4
        Question 2
            Answer 1
            Answer 2
            Answer 3
            Answer 4
        Question 3
            Answer 1
            Answer 2
            Answer 3
            Answer 4
    Theme 2 ==> Active == false
        Question 1
            Answer 1
            Answer 2
            Answer 3
            Answer 4
        Question 2
            Answer 1
            Answer 2
            Answer 3
            Answer 4
        Question 3
            Answer 1
            Answer 2
            Answer 3
            Answer 4

Thx!!!