AWS Certified Advanced Networking – Specialty ANS-C00 – Question397

A company hosts several applications in the AWS Cloud across multiple VPCs that are connected to a transit gateway. Redundant AWS Direct Connect connections and a Direct Connect gateway provide private network connectivity to the company's on-premises environment.
During a maintenance window, the networking team adds eight VPCs. The application management team notices that there is no reachability between the newly created VPCs and the on-premises environment. Connectivity between all VPCs through the transit gateway is working as expected.
Which of the following are possible causes of the connectivity issues? (Choose two.)

A.
The prefixes that are advertised from the Direct Connect gateway to the on-premises router are shorter than the CIDR blocks of the newly created VPCs
B. The route tables for the newly created VPCs do not have the routes to the on-premises environment that point to the transit gateway attachment
C. The on-premises route tables do not contain the exact CIDR blocks of the newly created VPCs
D. The route tables for the newly created VPCs have only summary routes for the on-premises environment that point to the transit gateway attachment
E. The prefixes that are advertised from the Direct Connect gateway to the on-premises router do not contain the CIDR blocks of the newly created VPCs