_______ may block reads, including those necessary to verify authentication.

Select the correct statement :

Delayed members are a ________ or a running “historical” snapshot of the data set

In sharded clusters, delayed members have limited utility when the __________ is enabled.

MongoDB indexes use a _______ data structure.

Select the correct statement :

MongoDB supports the creation of user-defined ascending/descending indexes on a ______ field of a document.

The ______ index is unique and prevents clients from inserting two documents with the same value for the _id field.

Select the wrong statement :

MongoDB also supports user-defined indexes on multiple fields called :