Right to object means that someone has the opportunity to object to receiving mailings. An example is requesting an opt-in (permission for mailings) during an order process or a contract conclusion. This often happens with a checkbox. You can select or deselect the checkbox depending on whether or not you want to receive mailings.
You may use a pre-checked opt-in checkbox. Someone can uncheck this. This is a less neat and friendly way, because people often overlook this.
You may send service messages or transactional mailings to your customers without an opt-in.
Please note: Offering the right to object is therefore different from giving an unsubscribe option in a mailing.