In GitOps, reconcilers ensure the actual state matches the desired state. Reconcilers may run inside the cluster (in-cluster) or outside (external). The choice depends primarily on operational scale and the complexity of reconciliation logic. “When determining reconciler placement, factors such as the size of the environment, the operational complexity of the reconciler, and the performance requirementsshould be evaluated. Incluster reconcilers are common for straightforward deployments, while external reconcilers may be chosen for large-scale or complex systems.” Thus, the most important considerations are clustersize and complexity of reconciler logic, making B correct. Reference: GitOps Related Practices(CNCF GitOps Working Group), GitOps Reconciler Guidelines. 

One of the four fundamental GitOps principles is Versioned and Immutable. This means that the entire system’s desired state must be stored in a Git repository with version control. Each change must be represented as a commit, and Git’s immutability guarantees a reliable, auditable history of how the system evolved. “The desired state isstored in a version control system. The record of truth is stored in an immutable history, and changes can be audited and reverted if necessary. This guarantees that the system’s configuration is versioned, immutable, and traceable.” Thus, configuration and infrastructure must be version-controlled and immutable, never changed directly in production. Reference: GitOps Principles (CNCF GitOps Working Group), Principle 2: The desired system state is stored as versioned and immutable.

In GitOps, Continuous Deployment (CD) follows after Continuous Integration (CI). CI is responsible for building and testing application code, while CD automates the delivery and deployment of these changes into runtime environments. The Git repository serves as the single source of truth, and when CI merges new changes into the main branch, CD reconciles the state of the environment to match what is declared in Git. “GitOps builds on the principles of DevOps by using Git as the source of truth for declarative infrastructure and applications. CI pipelines handle the integration and testing of code, and CD pipelines or agents automatically reconcile the desired state in Git with the actual state in the cluster.” This shows that CD is triggered after CI to handle deployment automation, ensuring systems remain in sync with what is declared in version control. Reference: GitOps Principles (CNCF GitOps Working Group), GitOps Working Group Terminology & Principles documents. 

A GitOps-managed Kubernetes cluster uses reconciliation loops to continuously compare the actual state of the system with the desired state declared in Git. When drift (divergence between declared configuration and live cluster state) is detected, the GitOps operator automatically reconciles the difference to bring the system back into alignment. “In GitOps, a reconciliation loop ensures that the desired state as declared in Git is continuously compared with the observed state of the system. If drift is detected, the system automatically takes corrective action to reconcile the difference and restore the declared configuration.” This ensures consistency, reliability, and self-healing. Manual intervention is not required for drift correction, as the automated reconciliation is a core principle of GitOps. Reference: GitOps Principles (CNCF GitOps Working Group), GitOps Principles Document — Principle 4: Software agents automatically pull the desired state declarations from the source and continuously observe actual system state, reconciling differences. 

Progressive delivery is a GitOps pattern used to release software gradually, reducing risks associated  with deploying new versions. Techniques such as canary releases, feature flags, and blue-green deployments allow teams to incrementally roll out changes, validate functionality with subsets of users, and minimize potential disruptions. “Progressive delivery builds on continuous delivery by enabling safer, incremental rollouts. This pattern reduces risk, improves reliability, enhances user experience, and allows for validation of features with a portion of users before wider release.” Therefore, progressive delivery is useful in multiple scenarios (not just one-time deployments or small teams), making option C correct. Reference: GitOps Patterns(CNCF GitOps Working Group), Progressive Delivery Patterns documentation.