Which of the following is an example of differentiation?

John and Nora each take time to learn each other's history of haggling before negotiating a contract.

Group members working on a project discuss why they are having conflict issues because of outside priorities.

Rebecca and Eduardo break down their issues of a contract from $3$ major points into $10$ smaller, minor points.

Sally and Phillip tell each other they make good points but still feel differently regarding which is the best Batman movie.