A pizza restaurant has recently experienced a decline in profit margin although sales have remained steady. An analysis of direct cost inputs revealed the following. A favorable materials price variance An unfavorable materials quantity variance A favorable labor rate variance An unfavorable labor efficiency variance Which one of the following is the most likely cause of the decline in the profit margin?
A.	The employees are working fewer hours than budgeted standard hours.
B.	The employees are being paid more than the budgeted standard rates.
C.	The new employees are still learning the recipes.
D.	The cheese supplier has raised prices.