Which of the following materials may not be used to secure a closet flange to the floor?

The correct answer is that brass plated bolts or screws may not be used to secure a closet flange to the floor. The primary reason is due to the properties of brass plated materials. While brass itself is a durable metal, brass plated items are often coated with a thin layer of brass over a less durable metal, which can corrode over time when exposed to moisture.

In situations like a closet flange, which is frequently under the influence of water, using materials that can deteriorate or corrode can lead to flanges becoming loose, creating leaks and potential damage to the structure. Unlike solid brass or stainless steel fasteners, which are resistant to rust and corrosion, brass plated materials do not offer the same level of durability in wet conditions.

For securing closet flanges, fasteners made of solid materials like brass or stainless steel are preferred due to their strength and resistance to corrosion, ensuring a more reliable and long-lasting installation.