Which of the following description of ZooKeeper feature is wrong?

Which of the following description of ZooKeeper feature is wrong?
A . Updates sent by the client are applied in the order in which they were sent.
B . A message is received by more than half of the servers and it can be successfully written to disk.
C . Message updates can only succeed or fail with no intermediate status.
D . The number of ZooKeeper nodes must be an odd number.

Answer: D