Why might a diligent manager not investigate all variances?

Select one:

a. Diligent managers focus solely on unfavorable variances as these variances, once corrected, will impact the company positively.

b. Diligent managers focus solely on favorable variances as improving these variances will dramatically increase the companys bottom line.

c. Diligent managers try to investigate most variances except those associated with fixed costs, as fixed cost variances cannot be reduced until the next fiscal period.

d. Diligent managers rarely investigate all variances because there is a cost associated with identifying the causes of variances. If all variances were investigated the costs of investigation could well exceed the benefits from that investigation.