Which of the following treatments should be avoided for clients allergic to iodine?

Clients who are allergic to iodine should avoid treatments that contain seaweeds or algae because these substances often have high iodine content. Algae, specifically, is known to absorb trace elements including iodine from the water in which it grows.

In the context of body wraps, algae body wraps typically use algae products for their purported benefits, which can release iodine when applied to the skin. This poses a risk of an allergic reaction for individuals sensitive to iodine.

On the other hand, seaweed wraps, while they may also contain iodine, are not the best fit here as they could still be considered less safe for clients with iodine allergies. Clay treatments and hydrating masks generally do not involve any iodine-containing ingredients, making them safer options for such clients. Therefore, the algae body wrap is the recommended treatment to avoid in this scenario.