Which material among nozzle options is least resistant to wear?

Brass is indeed one of the less durable materials compared to the others listed when it comes to wear resistance. It is an alloy of copper and zinc and is often selected for its good machinability and corrosion resistance. However, brass can be softer and more prone to wear and abrasion over longer periods, especially when used in high-friction situations or when subjected to harsh chemicals.

In contrast, materials like stainless steel are known for their high resistance to wear and corrosion due to their composition, making them ideal in settings where durability is paramount. Aluminum, while lighter and easier to work with, also tends to wear out more quickly under similar conditions compared to stainless steel but can offer a different balance of properties. Plastic, depending on its grade and type, may exhibit wear resistance suitable for certain conditions, but it might lack strength and durability when heavy wear is expected.

Therefore, brass is the least resistant to wear among the options, making it the correct choice for this question due to its comparatively softer nature and susceptibility to degradation over time.