A Customer Currently Uses XtremIO Native Remote Replication with Four

A customer currently uses XtremIO native remote replication with four RPAs and a 1 GB WAN link to asynchronously protect all production data. Management has decided that all data stored on the XtremIO must now be protected at the disaster recovery site by synchronous replication. How can this be achieved?

A) Set the Link Policy to Synchronous, Dynamic by throughput
B) Purchase four additional RPAs.
C) Set the Link Policy to Synchronous, Dynamic by latency
D) Use a VPLEX splitter