DOCS-154 final review edits

Author: Bob Grabar

source/core/replication-internals.txt

@@ -303,7 +303,7 @@ Pre-Fetching Indexes to Improve Replication Throughput
 ------------------------------------------------------
 
 By default, secondaries will in most cases pre-fetch :ref:`indexes`
-associated with a query to improve replication throughput.
+associated with the affected document to improve replication throughput.
 
 You can limit this feature to pre-fetch only the index on the ``_id``
 field, or you can disable this feature entirely. For more information,