public BasicCardResponse(string title, string subtitle, string imageUrl, string accessibilityText)
 {
     BasicCard = new BasicCard
     {
         Title    = title,
         Subtitle = subtitle,
         Image    = new Image {
             AccessibilityText = accessibilityText, Url = imageUrl
         }
     };
 }
 public BasicCardResponse(string title, string subtitle, string formattedText)
 {
     BasicCard = new BasicCard {
         Title = title, Subtitle = subtitle, FormattedText = formattedText
     };
 }
 public BasicCardResponse(string title, string subtitle)
 {
     BasicCard = new BasicCard {
         Title = title, Subtitle = subtitle
     };
 }