Which tax provision allows Michael to avoid including his reimbursed dinner expenses in gross income?

Michael can avoid including his reimbursed dinner expenses in gross income due to an accountable-type plan, which is a specific structure for employee reimbursement arrangements that meets certain criteria established by the IRS. In an accountable plan, expenses are reimbursed to employees provided that they meet the following conditions: the expense must have a business connection, the employee must adequately account for the expenses to the employer, and any excess reimbursement must be returned to the employer.

This structure allows Michael to exclude the reimbursed expenses from taxable income, as they are considered to be a reimbursement rather than income. By contrast, under a nonaccountable plan, reimbursements would need to be included in gross income, as there is no requirement for employees to substantiate their expenses or return any excess amounts to the employer.

The other options mentioned do not specifically address the imposition of tax liabilities on reimbursed expenses in the same way that an accountable plan does. A corporate tax deduction refers to the tax treatment of expenses at the corporate level, while an employee benefit plan may encompass a wider range of employee compensation benefits and not specifically address reimbursement of expenses. Therefore, the accountable-type plan is the only option that allows Michael to exclude these reimbursements from gross income effectively.