Maintenance charges are in the nature of . . . . . . . . expenses.

The correct answer is: B. Variable

Maintenance charges are expenses that vary depending on the level of use or activity. For example, the maintenance charges for a car will be higher if the car is driven more often.

Fixed expenses are expenses that do not vary with the level of use or activity. For example, the rent for an apartment is a fixed expense, regardless of how often the apartment is used.

Semi-variable expenses are expenses that have both fixed and variable components. For example, the cost of electricity is a semi-variable expense, because it includes a fixed charge for the connection to the power grid and a variable charge for the amount of electricity used.

I hope this helps!