In Estimating External Supply for Human Resources,demographic Trends Analysis Is

In estimating external supply for human resources,demographic trends analysis is:

A) useful,because tendencies are usually known years in advance of their impacts
B) less than useful,as demographic projections tend to be reactive and unreliable
C) ineffective,as information about trends is not often available and hard to obtain
D) in contravention of the Canadian human rights act
E) legal,but socially unacceptable