Question

In the ________ phase of the relationship escalation model, partners begin to take part in activities as a couple, and people begin to see them as a pair

Answer 1

I believe the correct answer is integration.
This is the moment where two people in a relationship can finally say they are officially in a relationship and want to be with each other. People now start seeing them as a real couple, and not just two people fooling around, and they start doing a lot of activities together.