Alex Quit Smoking and His Cravings for Cigarettes Have Reduced

Multiple Choice

Alex quit smoking and his cravings for cigarettes have reduced significantly.One day he had very strong cravings again as he was walking home from work.If Alex asked you for advice,which of the following would be an appropriate response

A)  If the cravings came back, then he might never be able to truly get rid of his addiction. 
B)  If the cravings came back, then it is evidence of a biological rather than psychological addiction. 
C)  Spontaneous recovery is triggered by the drug, so he must not have quit completely. 
D)  Spontaneous recovery of those cravings is normal, and it will diminish over time.