Which one is necessary for MRP$?$

$($I$)$ accurate inventory records

$($II$)$ accurate demand forecasts

$($III$)$ accurate holding and backordering costs

$($IV$)$ accurate bills of materials

Yanitiniz:

I, II$,$ III, and IV

I and II only

I, III, and IV only

$t,t,$ and $1+t$ only

I, II$,$ and IV only