A company operates a fleet of servers on premises and operates a fleet of Amazon EC2 instances in its organization in AWS Organizations. The company's AWS accounts contain hundreds of VPCs. The…

Creating and sharing a Transit Gateway across accounts using AWS Resource Access Manager (AWS RAM) provides a scalable and central hub for connecting hundreds of VPCs to on-premises networks efficiently.

This option is a partial duplicate of option E and does not encompass the full solution for controlling communication and managing operational effort.

Transit Gateway route tables allow for fine-grained control over which VPCs and VPNs can communicate with each other through explicit route table associations and propagations, minimizing operational overhead compared to managing individual VPC peering routes.

VPC peering connects two VPCs directly and does not scale well for hundreds of VPCs, making it high operational effort to manage routing and connectivity across a large number of connections.

Configuring attachments for all VPCs and VPNs to the Transit Gateway is essential for establishing the connectivity paths required for both inter-VPC and hybrid cloud communication.

Setting up route tables on each VPC and VPN directly would require immense operational effort for hundreds of VPCs, as individual route table management for inter-VPC communication is not scalable.