Explanation : The condition that all the data of the global relation must be mapped into the fragments, that is, it must not happen that a data item which belongs to a global relation does not belong to any fragment, is called Completeness condition. In distributed system it is convenient that fragment to be disjoint, so that the replication of data can be controlled explicitly at the allocation level.this is called Disjointness condition To reconstruct any global relation from its fragment is called Reconstruction condition. The formation of no. of fragments into a cluster is called Aggregation condition. So, option (B) is correct.
Explanation : Decomposition of R into R1(C, A) and R2(A, B) is lossless. Because C → A, A → B. So, C → AB can be derived and there is no loss. Decomposition of R into R1(A, B) and R2(B, C) is lossy. Because A → B, C → B are derived but we can't derive C → AB, So it is lossy. So, option (C) is correct.