Which statement is not correct?

a. Location transparency means that database users do not need to know on which node the required data reside.

b. Fragmentation transparency refers to the fact that users can execute global queries, without being concerned with the fact that distributed fragments will be involved, and need to be combined, to perform the query.

c. Transaction transparency refers to the fact that the distributed database can be accessed and queried in a uniform fashion, regardless of the different database systems and APIs that may be involved.

d. Replication transparency means that different replicas of the same data item will be automatically kept consistent by the database system and updates to one replica will be propagated transparently (be it synchronously or asynchronously) to the other copies of the same data item.