The Main Disadvantage(s)of Trial-And-Error Techniques Used for Aggregate Operations Planning

Multiple Choice

The main disadvantage(s) of trial-and-error techniques used for aggregate operations planning is (are) :

A) that they are expensive to do.
B) that they may not result in the best plan.
C) that they take a long time to do.
D) that they require the use of a computer.
E) All of the choices are disadvantages.