A bedridden patient is less likely to develop bed sores while lying on a water bed. This is because:

D: A water bag mattress flexes around a patient’s body so that it conforms more closely to their curved shape. Consequently, the area of contact between the patient and the supporting surface is increased. This increased area means that the pressure will be decreased. This lower pressure is less likely to compress the blood vessels that supply the skin and so circulation will not be cut off. Hence bed sores (ulcers) will be avoided.