Telerik.ReportViewer.Mvc.SendEmail class in Telerik Reporting ASP.NET MVC does not contain fields "Cc", "Subject", "Body" (https://docs.telerik.com/reporting/t-telerik-reportviewer-mvc-sendemail)
But JS documentation dontains such fields (https://docs.telerik.com/reporting/html5-report-viewer-jquery-fn-telerik-reportviewer#sendEmailOption).
I'm using the latest version of kendo ui and telerik reporting.