Which sieve number represents the finest screen?

The finest screen among the given options is represented by the #200 sieve number. In sieve analysis, the sieve number indicates the number of openings per inch in a screen used for separating materials. A higher sieve number corresponds to smaller openings, meaning that a #200 sieve has finer openings than #90, #135, or #175 sieves.

The #200 sieve allows particles that are 0.074 millimeters or smaller to pass through, effectively screening out larger particles. This makes it an essential tool in applications where precise particle size distribution is crucial, such as in constructing mixes for concrete or in quality control for granular materials. Understanding the specifications of sieve sizes is critical for millwrights, as it affects material handling and processing in various industrial applications.