In the code, you create one instance of GreenBookAnnouncementResponse, set its properties, and then add it to lstGreenBookAnnounce. Later in the code, you modify the properties of the same greenBookAnnouncementResponse object. There is no additional object creation or addition to lstGreenBookAnnounce in the later part of the code.So, only one instance of GreenBookAnnouncementResponse is added to lstGreenBookAnnounce. Any changes made to greenBookAnnouncementResponse after adding it to the list will affect the same object in the list.