Suppose no one has at least three friends, everyone has at most two friends, six people have at most 12 friends, and seven pairs of friends are known, *** 14 friends, which is contradictory, so at least one person has at least three friends.

Consider the person who has the most friends. He has at least three friends B, C and D, and at least two of them are friends. Let's make it B and C, then ABC will be friends with each other.

Hope to adopt ~ thank you!