Which of the following is prohibited in toilet facilities?

Using toilet facilities for storage is prohibited because it undermines the primary purpose and cleanliness of restroom facilities. Toilet areas should be maintained to ensure they are hygienic and accessible for personal use. When storage items are placed in these areas, they can lead to unsanitary conditions, make it difficult for clients to use the facilities, and create a potential health hazard.

Maintaining clean and functional restroom facilities is crucial in any cosmetology setting, as it reflects professionalism and care for client comfort and safety. The other options focus on various regulations regarding restroom functionality and use, but option B specifically addresses the misuse of the space designated for hygiene, which can directly impact the overall sanitation standards of the establishment.