In “Read Concern and Read Preferences” lab exercise the question is when 2 out of 3 nodes of the replica set are down “Which of these readPreferences will allow you to read data from this [remaining] node?”. The only remaining node will be a secondary even if it were the replica set primary to begin with.
The correct answer is considered to be all except the “primary” itself.
I’m questioning the “nearest” choice. I don’t consider that to be one of the correct answers. That “nearest” node could be one of the 2 down nodes which happened to be the nearest because it had the least network latency WHEN IT WAS UP. The remaining node could have originally had the worst network latency. Wouldn’t the read fail because the OLD “nearest” is unreachable now. Just as if we had “primary” as the read preference and it is no longer a primary.