Answer:
a) an unfavorable raw materials usage variance
Step-by-step explanation:
Material price variance
A material price variance occurs where materials are purchased at a price either lower or higher than the standard price. A favorable variance is recorded where the actual total cost of materials is lower that the standard cost. While an adverse variance implies the opposite
Material usage variance
A material usage variance occurs when the standard quantity required to active a particular level of production is higher or lower than than the actual actual quantity used. A favorable variance would mean than less quantity of materials were used than the standard to achieve a given output level. And an adverse variance would mean the opposite
Relationship between Usage variance and Price variance
Where savings are made from purchase of cheap and inferior quality materials these might lead to an unfavorable (adverse) usage variance by a greater value .This is so because workers might need to use a larger quantity ( more than the standard required) of a low-quality materials to achieve production.