Madden's Camera Shop has prepared the following flexible budget for September and is in the process of interpreting the variances. F denotes a favorable variance and U denotes an unfavorable variance. Flexible Variances Budget Price Efficiency Material A $25,000 $1 80OU $1 10OF Material B 33,000 60OF 20OU Material C 45.000 1 60QU 2, 10OF The explanation that lower-quality materials were purchased is most likely for O A. Material A OB. Material B O C. Material C O D. both Material A and C