What are two point-to-multipoint overlay tunneling strategies that are used in transitioning to IPv6 (choose two)?

A.
ISATAP

B.
6to4

C.
Nat64

D.
Dual-stack

Explanation:
https://www.cisco.com/c/en/us/td/docs/ios-xml/ios/interface/configuration/xe-3s/ir-xe-3s-book/ip6-6to4-tunlsxe.html

“The key difference between automatic 6to4 tunnels and manually configured tunnels is that the tunnel is not point-to-point; it is point-to-multipoint.”
https://www.cisco.com/c/en/us/td/docs/ios-xml/ios/interface/configuration/xe-3s/ir-xe-3s-book/ip6-isatap-xe.html
“ISATAP Point-to-multipoint tunnels that can be used to connect systems within a site.”