public class BlanksTaskCreateViewModel
    {
        public Guid TaskID { get; set; }
        public String Instruction { get; set; }
        public List<BlanksQuestionCreateViewModel> Questions { get; set; }

    }

public class BlanksQuestion:TaskQuestion
    {
      //  public Guid TaskID { get; set;}
        public virtual BlanksTask Task { get; set; }
        public virtual ICollection<BlanksAnswer> Answers { get; set; }
    }

public class BlanksQuestionCreateViewModel
    {
        public Guid QuestionID { get; set; }
        public String Question { get; set; }
        public int QuestionIndex { get; set; }
        public IList<BlanksAnswerCreateViewModel> Answers { get; set; }

    }

 public class BlanksAnswerCreateViewModel
    {
        public Guid BlanksQuestionID { get; set; }
        //public virtual BlanksQuestion BlanksQuestion { get; set; }
        public Guid BlanksAnswerID { get; set; }
        public String Answer { get; set; }
        public CharIndex Index { get; set; }

    }

public class BlanksAnswer : TaskAnswer
    {
       [ForeignKey("Question")]
       public Guid QuestionID { get; set; }
       public virtual BlanksQuestion Question { get; set; }
    }