Which One of the Following Statements About Access Control Matrices

Multiple Choice

Which one of the following statements about access control matrices is true?

A) In an installation with a large number of users and number of files, the matrix would be quite small.
B) Because allowing access to a file is the exception rather than the rule, the matrix will be rather dense.
C) The entry a_ij is 1 if user i is allowed access to file j.
D) The entry a_ij is 1 if user i may not be access file j.