Items that must be replaced with clean items for each client include:

The correct answer focuses on the necessity of replacing tools that come into direct contact with a client's skin or products to maintain hygiene and prevent cross-contamination. Makeup brushes and spatulas are categorized as reusable items that require proper sanitation between clients. To ensure safety and uphold health standards, it is critical to use clean brushes and spatulas for each client rather than reusing them without adequate cleaning.

In contrast, single-use cotton pads are designed for one-time use, meaning they should not be reused at all; thus, they do not require replacement in the same context as reusable items. Furniture typically does not need to be replaced for each client; rather, it should be cleaned and sanitized. Wax pots, while important to keep clean, do not necessarily require a new pot for every client, so they may not fit the same criteria as tools that directly attach to skin.