Which of these items must be removed when using AED pads?

When using AED pads, bulky clothing must be removed because it can interfere with the proper adhesion of the pads to the patient's chest and may prevent effective delivery of the defibrillation shock. AED pads need to establish full contact with the skin to ensure that the electrical current travels effectively through the body. In situations where clothing is preventing this contact, especially if it is thick or layered, removing it is crucial.

While it is important to ensure that the chest is clear of any obstructions, removing all clothing (as suggested in another option) is not always necessary, as some types of clothing may be thin enough not to hinder the AED's function. Jewelry, including rings, can generally be left on unless it poses a risk of contact with the pads or if it is in an area where the pads are to be placed. Therefore, focusing on removing bulky clothing is the best practice for effective AED use.