A. Factory management costs will generally not differ among the options, therefore they are not relevant.
B. Depreciation costs will generally not differ among the options, therefore they are not relevant.
C. General office costs will generally not differ among the options, therefore they are not relevant.
D. In the decision to make-versus-buy decision you want to look only at relevant costs that differ among the options. Relevant costs include both avoidable fixed and variable costs.
