What is used to forward BUM traffic to all endpoints in the same broadcast domain?

In a Cisco ACI Multi-Site fabric, the Inter-Site BUM Traffic Allow option is enabled in a specific stretched bridge domain .

What is used to forward BUM traffic to all endpoints in the same broadcast domain?
A . ingress replication on the spines in the source site
B . egress replication on the source leaf switches
C . egress replication on the destination leaf switches
D . ingress replication on the spines in the destination site

Answer: D

Explanation:

Reference: http://yves-louis.com/DCI/?p=1277