Penetration testing engagement is the correct option for the greatest level of effort.

A penetration testing engagement requires skilled human testers to perform deep reconnaissance manual exploitation and chaining of vulnerabilities across systems and business logic. It requires custom attack planning repeated validation and detailed reporting so it typically demands far more time coordination and expertise when a platform spans many interdependent services.

Automated vulnerability scanning uses tools to find known weaknesses and configuration issues and it is useful for broad baseline coverage. It runs faster and at scale and it cannot replicate the creative manual work needed to exploit complex interactions so it does not require the greatest effort.

Social engineering exercises can be resource intensive and require careful planning and ethical controls but they target human behavior rather than chaining technical exploits across many services. They are often narrower in technical scope than a full penetration testing engagement.

Cloud Security Command Center assessment is a cloud vendor product that automates discovery and risk identification for cloud resources and it supports continuous monitoring. It is helpful for cloud posture management but it is vendor specific and far less labor intensive than a comprehensive manual penetration test.

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