Two Costs at Bradshaw Company Appear Below for Specific Months

Two costs at Bradshaw Company appear below for specific months of operation. $\begin{array}{llrr}&\text { Month}&\text { Amount}&\text { Units Produced }\\\text { Delivery costs } & \text { September } & \$ 40,000 & 40,000 \\& \text { October } & 55,000 & 60,000 \\\text { Utilities } & \text { September } & \$ 84,000 & 40,000 \\& \text { October } & 126,000 & 60,000\end{array}$ Which type of costs are these?

A) Delivery costs and utilities are both variable.
B) Delivery costs and utilities are both mixed.
C) Utilities are mixed and delivery costs are variable.
D) Delivery costs are mixed and utilities are variable.