The correct answer is: A. fixed charges.
Fixed charges are costs that do not vary with the level of activity. They are typically incurred on a regular basis, such as monthly or annually. Insurance and garage rent are examples of fixed charges.
Maintenance charges are costs that are incurred to keep an asset in good working condition. They typically vary with the level of use of the asset. For example, the cost of oil changes for a car will vary depending on how often the car is driven.
Operating charges are costs that are incurred to operate an asset. They typically vary with the level of production or output of the asset. For example, the cost of electricity for a factory will vary depending on how much production is taking place.
Running charges are costs that are incurred to keep a business running. They typically include costs such as rent, utilities, and salaries. Running charges are not directly related to the production of goods or services.
In conclusion, insurance and garage rent are fixed charges because they do not vary with the level of activity.