Step 1: Anchor the answer to the WHO timeline for tuberculosis control. The Stop TB Strategy replaced the earlier DOTS-only framework and was rolled out by the WHO in 2006.
Step 2: Its accompanying roadmap, the Global Plan to Stop TB, explicitly covered the decade 2006 to 2015, which fixes the launch year firmly at 2006.
Step 3: The strategy still keeps DOTS at its heart and is monitored through case detection, treatment success, incidence, prevalence and death rates, all aligned with the Millennium Development Goals. Targets included a 50 percent cut in prevalence and deaths versus 1990 by 2015.
Step 4: None of the other listed years marks this launch, so 2006 is correct.
\[\boxed{2006}\]