Answer:
D. unfavorable fixed overhead flexible minus budget variance
Explanation:
As the cost of the equipment is increasing the fixed efficiency and idle capacity variance would be unfavorable resulting in an unfavorable fixed overhead flexible minus budget variance.
The expenses of the machinery are the fixed indirect costs which result in fixed overhead variances. Since it is related to the working of the machinery it would result in efficiency and idle capacity variances that in turn would give unfavorable fixed overhead of the flexible minus budget variance.