Onyx Company has prepared a static budget at the beginning of the month. At the end of the month, following information has been retrieved from the records.

Static budget:

Sales volume: 2,000 units: Price: $50 per unit

Variable expense: $12 per unit: Fixed expenses: $25,000 per month

Operating income: $51,000

Actual results:

Sales volume: 1,800 units: Price: $58 per unit

Variable expense: $16 per unit: Fixed expenses: $35,000 per month

Operating income: $40,600

Calculate the flexible budget variance for operating income.

A) $4,500 U

B) $7,600 U

C) $2,800 U

D) $5,490 F