Problem 2. On the island, every resident is either a knight (always tells the truth) or a liar (always lies). Two residents are called of the same type if they are either both knights or both liars. A, B, and C are residents of this island. A says: "B and C are of the same type." What will C answer to the question "Are A and B of the same type?"
# Answer: “Yes".

Solution. Let's go through the options of who A might be.

If A is a knight, then B and C are of the same type. If B is a knight in this case, then C is also a knight, and C will answer "Yes." If B is a liar, then C is also a liar, and will still answer "Yes." If A is a liar, then B and C are of different types. If B is a knight in this case, then C is a liar, and will answer "Yes," and if B is a liar, then C is a knight, and will still answer "Yes."

Thus, C will always answer: “Yes."