The correct answer is B. Bi annual basis . Steam traps should be tested periodically because failed traps waste energy, reduce heating efficiency, create water hammer risk, affect condensate return, and may damage steam-system reliability. Weekly testing would normally be excessive for a general program unless a specific critical application requires unusually frequent checks. Quarterly testing can be appropriate for high-pressure, high-consequence, or problem-prone systems, but the generally accepted practical frequency in this CRL-style context is bi-annual testing. A six-month interval gives the organization a reasonable balance between defect detection and inspection effort. Steam trap testing is part of Asset Condition Management because it uses condition evidence—often ultrasound, temperature comparison, or trap-performance checks—to detect failed-open, failed-closed, leaking, or malfunctioning traps before they create larger system losses. The key reliability principle is that the inspection interval should reflect failure consequence, trap population, operating pressure, and system criticality. From the provided choices, bi annual basis is the most appropriate best-practice answer for routine steam trap testing.