Which of the following is not considered a "trade or business" expense?

A parking ticket paid on a business vehicle is not considered a "trade or business" expense because it does not directly relate to the operation of the business or the generation of income. Trade or business expenses are typically those that are necessary and ordinary for the functioning of a business.

Interest on business indebtedness, property taxes on business property, and depreciation on business property all qualify as trade or business expenses because they are directly related to the costs incurred in operating a business. Interest payments are necessary for financing business operations, property taxes are obligations that arise from owning business property, and depreciation reflects the wear and tear or decrease in value of business assets over time, which is recognized as a legitimate expense.

In contrast, a parking ticket is a penalty incurred due to a failure to comply with municipal regulations, which does not serve a productive purpose in the context of business activities. As such, it cannot be deducted as a business expense under tax regulations.