Answer:
The correct answer is option c.
Step-by-step explanation:
Variable cost is the cost incurred on the variable factors. In the production process, to increase output more variable inputs are hired. So, the total variable cost will increase with an increase in production.
But the variable cost per unit is the variable cost incurred on a single unit of output. This will remain the same throughout the process and change only if there is a change in input prices.