Which two are Features of Hadoop’s rack topology?

A.
Configuration of rack awareness is accomplished using a configuration file. You cannot
use a rack topology script.

B.
Even for small clusters on a single rack, configuring rack awareness will improve
performance.

C.
Rack location is considered in the HDFS block placement policy

D.
HDFS is rack aware but MapReduce daemons are not

E.
Hadoop gives preference to Intra rack data transfer in order to conserve bandwidth