Which of the following conditions would require immediate action during an inspection of a sprinkler system?

Immediate action during an inspection of a sprinkler system is crucial when certain conditions are identified that could compromise the functionality and safety of the system. An obstruction in water flow can prevent the proper discharge of water during an emergency, potentially leading to catastrophic consequences in a fire situation. Removing or addressing any such blockage is essential to ensure that the system performs as intended.

Similarly, corroded pipes indicate deterioration that might lead to leaks or complete failure of the system. Corrosion can also compromise the integrity of the water supply and pressure, which are vital for effective sprinkler operation. If left unaddressed, corroded pipes can lead to system inefficiency, risk of water damage, and loss of critical firefighting capabilities.

Given that both of these conditions represent serious threats to the reliability and effectiveness of the sprinkler system, taking immediate action is necessary. Therefore, acknowledging both obstructions in water flow and corroded pipes as requiring urgent attention correctly supports the need for prompt remediation in the maintenance of fire sprinkler systems.