Which of the following expenses is NOT deductible if unreimbursed?

The correct choice indicates that tax preparation fees for non-business-related matters are not deductible if they are not reimbursed. This aligns with the changes in tax legislation, particularly the Tax Cuts and Jobs Act, which has significantly limited the ability of individuals to deduct personal expenses, including tax preparation fees associated with personal tax matters.

In general, unreimbursed expenses incurred by individuals are subject to strict criteria for deductibility. While certain expenses may be deductible if they are related to a business or trade, personal expenses, like those for tax preparation concerning non-business activities, do not qualify for deductions.

On the other hand, categories such as employee safety gear, business mileage, and union dues typically align with business-related expenses and may be deductible under certain conditions. Employee safety gear is necessary for job performance, business mileage costs are related to travel for work purposes, and union dues are often deductible as necessary costs for maintaining employment in a specific industry.

Thus, the key differentiation here is the type of expense and its relevance to business activities versus personal expenses.