The basic difference between obsession and compulsion is:

(A) The former involves preoccupation with certain thoughts while the later involves preoccupation with certain actions
(B) There is no difference between the two disorders
(C) The former is diagnosed along with the Axis III of DSM-IV whereas the later is diagnosed along with the Axis II of DSM-IV
(D) The former is a mood disorder whereas the later is an anxiety disorder