A customer needs a remote data copy， data migration， and off-site backup solution. The solution cannot impact application performance. The sites are over continental distances.  Which  characteristic of DS8700 Global Mirror makes it a good fit for this customer（）

A.it provides synchronous mirroring on both sides

B.it can be implemented withoutFlashCopy volumes at the target site

C.with Global Mirror， the Metro Mirror functions can be used over continental distances

D.it has almost no impact on application performance because of its extremely short and adjustable coordination time