The reconciliation loop is a fundamental GitOps principle. It continuously compares thedesired state(stored in Git) with theactual state(running in the system). When a divergence (drift) is detected, the reconciler automatically corrects the system to match the desired state.
"The reconciliation loop ensures the system is continuously converging toward the declared desired state.
Whenever the actual state deviates, the loop reconciles the system to match the desired state." Thus, the correct answer isC.
References:GitOps Principles (CNCF GitOps Working Group).

TheDesired Statein GitOps is the declarative specification of how the system should behave. It is stored in Git and serves as the reference point for reconciliation against the actual state.
"The desired state is a complete specification of the system stored in Git. It acts as the blueprint from which the actual state is continuously reconciled, ensuring the system remains consistent and reproducible." Thus, theprimary purpose of Desired Stateis to act as ablueprintto recreate and ensure consistency of the system.
References:GitOps Terminology (CNCF GitOps Working Group).

Blue-Green deployments are aprogressive delivery patternwhere two environments exist: Blue (current version) and Green (new version). The new version is deployed in parallel, and once validated, traffic is switched over from Blue to Green.
"Blue-Green deployments provide zero-downtime releases by running two production environments: one active and one idle. A new version is deployed to the idle environment, tested, and when ready, traffic is switched to it." Thus, the correct description isA.
References:GitOps Patterns (CNCF GitOps Working Group), Progressive Delivery patterns.

A fundamental GitOps principle is that reconciliation isautomated and continuous. Software agents (e.g., controllers like ArgoCD or Flux) continuously pull desired state declarations from Git repositories and reconcile them with the actual state.
"Software agents automatically pull the desired state declarations from the source of truth and continuously reconcile the actual state to match." Thus, the correct answer isC.
References:GitOps Principles (CNCF GitOps Working Group),Principle 4: Continuously reconciled.

Configuration as Codeis a GitOps-related practice where configurations are stored as declarative definitions in version control. Helm charts, for example, allow applications deployed on Kubernetes to have both their container images and configuration specified declaratively.
"Configuration as Code enables teams to manage application and infrastructure configuration in version control systems, using declarative approaches such as Kubernetes manifests or Helm charts. This ensures repeatability, automation, and auditability." Thus,Helm chartsare a prime example of this practice, makingCcorrect.
References:GitOps Related Practices (CNCF GitOps Working Group), Configuration as Code.