$\frac{W\text{W}\text{h}\text{a}\text{t}\text{e}\text{s}}{E}$ Which demonstrates a scenario with no opportunity cost?

It's Friday night and you stay up late talking and hanging out with your friends.

The chemistry club is giving out free pizza for lunch to all who come to their meeting to get it$.$

Naomi, age $8,$ is at a bookstore and chooses to buy a book about a young wizard instead of buying a math textbook that she would probably never open.

Chez Moi and Chez Nous, two premiere French restaurants with three Michelin stars, both offer you a full time sous chef job at the same salary. You are ecstatic because you know it is a win$-$win scenario and choose to work for Chez Nous.

All of these scenarios have an opportunity cost.