HDFS behavior when a file got corrupted

Question

I find Sample Questions on cloudera exam I believe the answer is D. Agree ??

Question 1 You use the hadoop fs -put command to add sales.txt to HDFS. This file is small enough that it fits into a single block, which is replicated to three nodes within your cluster. When and how will the cluster handle replication following the failure of one of these nodes?

• A. The cluster will make no attempt to re-replicate this block.
• B. This block will be immediately re-replicated and all other HDFS operations on the cluster will halt while this is in progress.
• C. The block will remain under-replicated until the administrator manually deletes and recreates the file.
• D. The file will be re-replicated automatically after the NameNode determines it is under-replicated based on the block reports it receives from the DataNodes.

Answer 1

Yes. It's D. When Namenode determines the datanode is no longer active it'll make one of the datanodes that has the given block to replicate to another node.