A. AWS Direct Connect neither provides BGP nor provides the failover.
B. AWS Direct Connect recommends to have the same configuration set up in a multi AZ zone to prevent such loss in connections.
C. AWS Direct Connect recommends that you request and configure two dedicated connections to AWS either using BGP Multipath (Active/Active) connection or the failover (Active/Passive) connection.
D. AWS Direct connect does not have a provision to prevent the situation but when you design the system, it is recommended to request a back-up instance to which the traffic can be re-routed.