How can a subnet's validator participation be managed over time?

• A. Validators are fixed and cannot rotate.
• B. Governance can rotate and upgrade validators as needed.
• C. Validators rotate automatically by the X-Chain.
• D. Validators are assigned randomly from the general public.

Answer: (B)

The main idea is that a subnet’s validator membership is controlled through governance, allowing changes over time. Subnets in Avalanche can have their validator set updated by on-chain decisions made by the subnet’s governance process. This lets operators rotate in or out validators and upgrade the subnet’s configuration or VM as needed, keeping participation aligned with policy, performance, or security goals.

This is why the option about governance rotating and upgrading validators is the best fit: it captures the intentional, managed, and adaptable approach to validator participation. In contrast, saying validators are fixed and cannot rotate isn’t accurate because governance-enabled rotation is a designed feature. Saying rotation happens automatically by the X-Chain isn’t correct—the protocol relies on governance decisions, not automatic self-rotation. And assigning validators randomly from the general public doesn’t reflect how subnets define their validator set and approval processes.