public void GetExamFromAPI() { var examService = new ExamService(); var candidateService = new CandidateService(); var exam = examService.GetLatestOpenExamWithQuestionOptions(candidateService.GetCandidate("*****@*****.**").Id); exam.Questions.ToList().ForEach(x => x.Options.ToList().ForEach(y => { var relatedQuestions = examService.GetRelatedQuestions(y.Id); var answer = new Answer { AnswerText = string.Empty, Level = x.Level, ScorePoint = x.ScorePoint, Id = Guid.NewGuid(), //need to use DbContext.QuestionsOption.Attach() if you want to use this Option = new Option { Id = y.Id, IsSelected = y.IsSelected }, Exam = new Exam { Id = exam.Id, Text = exam.Text } }; var answerReturned = examService.AddAnswer(answer); Debug.WriteLine(relatedQuestions.Count); })); Assert.IsNotNull(exam); }