In Order to Deduct a Portion of the Cost of a Business

In order to deduct a portion of the cost of a business meal which of the following conditions must be met?

A) A client (not a supplier or vendor) must be present at the meal.
B) The taxpayer or an employee must be present at the meal.
C) The meal must occur on the taxpayer's business premises.
D) None of these choices is a condition for the deduction.
E) All of the choices are conditions for a deduction.