FOr the lab session one answer seems to be wrong.
The write operation will always return with an error, even if wtimeout is not specified.
Even though when a node is down, and w:3, the write operation waits indefinitely, I see the error because it was unable to connect to the node.
W NETWORK [ReplicaSetMonitor-TaskExecutor-0] Failed to connect to 192.168.103.100:27003, in(checking socket for error after poll), reason: Connection refused
Better we reword the answer.