What is a 'blue-green' deployment and how does it relate to SAD maintenance?

What is a 'blue-green' deployment and how does it relate to SAD maintenance?

• A. A deployment strategy that delays updates to avoid risk.
• B. A deployment strategy that reduces downtime by shifting traffic between two identical environments; supports safe maintenance.
• C. A deployment strategy that uses multiple data centers for load.
• D. A deployment strategy that migrates data to cold storage after release.

Answer: (B)