Insert ' Into A Database

My problem is that when I add a question and the question contains a ' (For instance: I'm going to the store), an error message shows up for 'm from I'm.
 
Here is my code. 
            SqlConnection myConnection = new SqlConnection("Server=???;Database=???;Persist Security Info=True;User ID=???;Password=???");
            SqlCommand insertCmd = new SqlCommand();
            insertCmd.CommandType = System.Data.CommandType.Text;
            insertCmd.CommandText = "INSERT INTO TestQuestions (unitChapterID, question, answerA, answerB, answerC, answerD, answer) VALUES ("
                + int.Parse(DropDownList3.Text.ToString()) + ", '"
                + questionAddBox.Text.ToString() + "', '"
                + aAddBox.Text.ToString() + "', '"
                + bAddBox.Text.ToString() + "', '"
                + cAddBox.Text.ToString() + "', '"
                + dAddBox.Text.ToString() + "', '"
                + answerAddBox.Text.ToString() + "')";

            insertCmd.Connection = myConnection;

            myConnection.Open();
            insertCmd.ExecuteNonQuery();
            myConnection.Close();