How many laboratories are in the Laboratory Response Network within the United States?

• A. 120 labs in the U.S
• B. 60 labs
• C. 200 labs
• D. 500 labs

Answer: (A)

The question tests understanding of how extensive the Laboratory Response Network is within the United States. The LRN is a nationwide system that links sentinel laboratories, which do initial screening, with more specialized confirmatory labs to handle verification and advanced testing. This setup requires a defined country-wide footprint to ensure samples can be collected and processed quickly from any region. The correct option reflects the established scale of the U.S. portion of the LRN, balancing wide geographic coverage with practical lab capacity. The other figures would imply too few or too many facilities compared with how the network is described and used in standard materials.