Which of the following best describes fixed expenses?

Fixed expenses are best described as expenses that remain constant over time. These are regular payments that do not vary from month to month, making it easier to predict and manage a budget. Common examples include rent or mortgage payments, insurance premiums, and loan payments, which typically have set amounts due at regular intervals.

In contrast, the other options describe different types of expenses. Fluctuating costs, for instance, can vary based on usage or external factors, making them unpredictable. Payments for discretionary spending pertain to non-essential purchases that can change based on personal choice and lifestyle. Additionally, costs that do not require budgeting suggests a lack of financial planning, which is not characteristic of fixed expenses, as they are indeed a critical component of a well-structured budget.