The correct option is Free.

Free is available for both personal accounts and organization accounts, which lets the nonprofit use the same plan name across both account types and keep billing straightforward.

Enterprise is an organization level offering and is not available to personal accounts, so it cannot satisfy the requirement to standardize across both account types.

Pro is only for personal accounts and does not exist for organizations, so it does not meet the goal.

Team is only for organization accounts and is not available for personal accounts, so it cannot be used across both account types.

Personal is not a current GitHub pricing plan and refers to an account type rather than a product plan, so it is not applicable. Older references that use similar wording are not part of the current product lineup.

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