Explanation:
Box 1 = Write and replicate data to every region synchronously
This is because the write concern is mapped to the default consistency level configured on your Azure Cosmos DB account2, which is strong in this case. Strong consistency ensures that every write operation is synchronously committed to every region associated with your Azure Cosmos DB account1. The request level consistency level of session only applies to the read operations of App11.
Box 2: That has the lowest estimated latency to the client
This is because the read operations of App1 will use the session consistency level that is specified in the request options. Session consistency is a client-centric consistency model that guarantees monotonic reads, monotonic writes, and read-your-own-writes within a session. A session is scoped to a client connection or a stored procedure execution. Session consistency allows clients to read from any region that has the lowest latency to the client.