DOCSP-51320: Document causal consistency

Author: mcmorisi

source/crud/transactions.txt

@@ -47,6 +47,35 @@ creating a new client each time.
    ``ClientSession`` with a different ``MongoClient`` results in operation
    errors.
 
+Causal Consistency
+~~~~~~~~~~~~~~~~~~
+
+.. sharedinclude:: dbx/causal-consistency.rst
+
+   .. replacement:: insert-one-method
+
+      ``insertOne()``
+
+   .. replacement:: update-one-method
+
+      ``updateOne()``
+
+   .. replacement:: find-one-method
+
+      ``find()``
+
+   .. replacement:: delete-one-method
+
+      ``deleteOne()``
+
+   .. replacement:: ReadConcern.MAJORITY
+
+      ``majority``
+
+   .. replacement:: WriteConcern.MAJORITY
+
+      ``majority``
+
 Sample Data
 ~~~~~~~~~~~