Ans: D. Secular(Ref Parks 24/e p69, 23ie p66, 22/c p63)Secular:Trend of gradual increase in number of non- communicable disease cases as compared to previous years.Implies changes in disease occurrence over long time period (several years or decades).Maybe progressive increase/decrease in disease occurrence.Hence, long-term trend.Eg:CHD, lung cancer & DM (non-communicable disease) - Consistent upward trend in developed countries.TB, typhoid fever, diphtheria & polio - Declined trend in developed countries.