Answer:
(A) favorable flexible budget variance for variable costs
Explanation:
As in the given case, the question is talking about the variable cost per unit that lead to the flexible budget variance instead of the sales volume variance
Since in the given scenario, the actual variable costs per unit were lower than the expected variable costs per unit that reflects the favorable and if the actual variable costs per unit were higher than the expected variable costs per unit so it would reflect the unfavorable variance