Which test measures the concentration of various components in urine?

Urinalysis is the correct choice because it specifically focuses on the examination of urine to assess its physical, chemical, and microscopic properties. This comprehensive assessment allows for the measurement of various components in urine, such as proteins, glucose, electrolytes, and specific gravity, among others.

In a urinalysis, both qualitative and quantitative evaluations are performed, making it a crucial tool for diagnosing different medical conditions, monitoring health status, and performing routine checks. The test provides valuable insights into kidney function, hydration status, and the presence of possible infections or disorders.

In contrast, the other choices—biochemistry, hematology, and serology—are different types of laboratory tests that focus on other bodily fluids or components. Biochemistry typically involves testing blood serum for metabolic and biochemical markers, hematology focuses on blood components and cell counts, while serology is related to the study of serum and the immune response to infections or autoimmune conditions. None of these tests specifically measure the concentration of components in urine as directly as a urinalysis does.