Answer: a.may increase while conversion costs decrease because the two are separately calculated and depend on separate costs.
Step-by-step explanation:
When the cost of production report is being used to analyze change in direct materials cost per equivalent unit when compared to the conversion cost per equivalent unit, we should note that an investigation may end up showing that the fluctuation in the the direct materials costs which then brings about an increase or a decrease.
Therefore, the correct option is A "may increase while conversion costs decrease because the two are separately calculated and depend on separate costs".