Question

which topic is best suited for a formal discussion?
the contents of a new textbook
the weekend plans of your friends
the best places to shop online for new shoes
the best cookbooks for learning to make thai food

Explanation:

Formal discussions typically involve academic - related or professional - like topics. The contents of a new textbook are an academic topic, while the other options are more casual or personal.

Answer:

the contents of a new textbook