The problem requires restricting admin access to Google Cloud APIs based on geographic location (Canada and Germany) and environment (development and production projects).
VPC Service Controls (VPC SC): VPC Service Controls is designed to create security perimeters around Google Cloud resources and services. Its primary purpose is to prevent data exfiltration and control access to Google Cloud APIs based on the context of the request, which includes the source IP address.
Extract Reference: "VPC Service Controls provides an extra layer of security defense for Google Cloud services that is independent of Identity and Access Management (IAM). While IAM enables granular identity-based access control, VPC Service Controls enables broader context-based perimeter security, including controlling data egress across the perimeter." (Google Cloud Documentation: "Overview of VPC Service Controls" -
Service Perimeters for Environments: Creating dedicated perimeters for development and production projects allows for logical separation of environments, which aligns with the "dedicated projects for development and production" structure.
Ingress Policies with Geographic Restrictions: VPC Service Controls uses "ingress rules" to define who and from where requests can enter a service perimeter. These ingress rules can be configured to allow access based on various attributes, including the source IP address of the request. By allowing access from specific IP ranges corresponding to Canada and Germany, you effectively restrict administrative access to APIs from those countries. You can define "access levels" (which can include IP subnets or geographical origins) and attach them to ingress policies.
Extract Reference: "To allow ingress to resources, VPC Service Controls evaluates sources and identityType attributes as an AND condition... You must specify an accessLevel or a resource (Google Cloud project or VPC network), or set accessLevel attribute to *." (Google Cloud Documentation: "Ingress and egress rules | VPC Service Controls" -
Extract Reference (for Context-Aware Access which underpins access levels): "You can create different types of Context-Aware Access policies for accessing apps: IP, device, geographic origin, and custom access-level attributes." (Google Workspace Admin Help: "Protect your business with Context-Aware Access" - - While this references Workspace apps, the underlying mechanism of Access Context Manager (used by VPC SC) supports geographic restrictions.
Let's evaluate the other options:
A. Create dedicated firewall policies... restrict access based on geolocations: VPC firewall rules operate at the network level (Layers 3/4) within a VPC. They control traffic between VM instances or to/from the internet for network services. They do not directly control admin access to Google Cloud APIs (e.g., via the console or gcloud CLI calls) originating from outside the VPC.
B. Activate the organization policy on the folders to restrict resource location: The Resource Location Restriction organization policy constraint restricts where new resources can be created or stored (e.g., data residency requirements). It does not restrict where administrators can connect from to manage these resources or access APIs.
D. Create dedicated IAM Groups... Grant access: IAM (Identity and Access Management) controls who can access what resources and what actions they can perform. It does not natively provide control over where the access originates from (e.g., country-specific IP addresses).
Therefore, VPC Service Controls with properly configured ingress policies based on source IP/Access Levels is the recommended and most effective method for restricting admin access to Google Cloud APIs by geographic location and environment.