I do not know what seems the problem in my code. I want to add the data to my database (using windows form) but whenever I refresh my database, no updates were observed. Thank you for your help. Here is my code:

public void btnSave_Click(object sender, EventArgs e)

            string question = txtQuestion.Text;
            string choice1 = txtbChoice1.Text;
            string choice2 = txtbChoice2.Text;
            string choice3 = txtbChoice3.Text;
            string choice4 = txtbChoice4.Text;
            string answer = txtbAnswer.Text;

        if (txtQuestion.Text.Trim().Length != 0 && txtbChoice1.Text.Trim().Length != 0 && txtbChoice2.Text.Trim().Length != 0 &&
                txtbChoice3.Text.Trim().Length != 0 && txtbChoice4.Text.Trim().Length != 0 && txtbAnswer.Text.Trim().Length != 0 &&
                (answer.Trim() == choice1.Trim() || answer.Trim() == choice2.Trim() || answer.Trim() == choice3.Trim() || answer.Trim() == choice4.Trim()))
                //connection to database
                Connection conn = new Connection();

                SqlCommand cmd = new SqlCommand("INSERT INTO Questions (Question, Choice1, Choice2, Choice3, Choice4, Correct_Answer) values (@Question, @Choice1, @Choice2, @Choice3, @Choice4, @Correct_Answer)", Connection.conn);
                cmd.Parameters.AddWithValue("@Question ", question);
                cmd.Parameters.AddWithValue("@Choice1", choice1);
                cmd.Parameters.AddWithValue("@Choice2", choice2);
                cmd.Parameters.AddWithValue("@Choice3", choice3);
                cmd.Parameters.AddWithValue("@Choice4", choice4);
                cmd.Parameters.AddWithValue("@Correct_Answer", answer);
                   DialogResult dialogResult = MessageBox.Show("Do you want to add another question?", "Question", MessageBoxButtons.YesNo);
                   if (dialogResult == DialogResult.Yes)
                       NewQuestions nNewQuestion = new NewQuestions();

                   else if (dialogResult == DialogResult.No)
                       Options nOptions = new Options();


And here is my database (in case it is needed):

CREATE TABLE "Questions"
    QuestionID int IDENTITY NOT NULL,
    Question VARCHAR(500) NOT NULL,
    Choice1 VARCHAR(50) NOT NULL,
    Choice2 VARCHAR(50) NOT NULL,
    Choice3 VARCHAR(50) NOT NULL,
    Choice4 VARCHAR(50) NOT NULL,
    Correct_Answer VARCHAR(50) NOT NULL,
    PRIMARY KEY (questionID)