why ComputEr DAtA BEComE imprECisE in 1980s
A．thE rElAtED progrAms on thE ComputEr wErE out oF DAtE.
B．morE AnD morE pEoplE DrEw wAtEr DirECtly From thE lAkE For Drink.
C．A hEAvy rAin hAppEnED ArounD 1980.
D．thE irrigAtion From thE sourCE wAtEr inCrEAsEs.