The correct option is Prepare phase.

The Prepare phase is where an organization defines its context and identifies principal stakeholders along with roles, responsibilities, risk management strategy, and resources before system specific activities begin.

The Prepare phase was introduced as the initial, organization level step in the NIST Risk Management Framework to ensure that senior leaders and stakeholders are aligned and that systems are managed within an agreed risk posture prior to categorization and control selection.

Select is incorrect because that phase focuses on choosing and tailoring security controls for a system after the system has been categorized and risk information is available.

Monitor is incorrect because that phase is about continuous monitoring of controls and ongoing assessment after authorization rather than defining organizational context or identifying stakeholders.

Categorize is incorrect because that phase addresses determining the information system impact levels based on FIPS 199 and it is a system level activity that follows the organization level preparations.

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