Waiter Evan needs to serve entrees (fried eggs, hamburger, cheeseburger, vegetable burger, soup, ham sandwich) to customers in chairs 1-6. Rules: Non-sandwiches at 3 & 4; Cheeseburger and hamburger not adjacent; Chair 5 won't sit next to ham eaters; Vegetable burger between fried eggs and cheeseburger, not chair 2; Hamburger not next to soup.
Question: To which customer should Evan serve the vegetable burger?
Options:
A. chair 2, B. chair 3, C. chair 4, D. chair 5, E. chair 6
Answer: D