Which two statements are true?

Which two statements are true?

A.
An internal BGP (iBGP) network can have Route-Reflectors within a Confederation.

B.
An internal BGP (iBGP) network cannot have Route-Reflectors within a Confederation because Confederation works between External Autonomous System (AS) numbers.

C.
Clusters are used in Route-Reflector schemes to avoid loops.

D.
A confederation uses confederation clusters to avoid routing loops.