Lancaster [1979] considers that an Information Retrieval System (IRS) comprises the following components:
(A). the document selection sub-system
(B). the indexing sub-system
(C). the vocabulary sub-system
(D). the searching sub-system
1
A, B and C
2
B, C and D
3
A, B, C and D
4
A, C and D
5
Question Not Attempted