Answer:
Collaboration.
Step-by-step explanation:
Collaboration is the act of unitedly acting together to come to a solution that best benefits everyone. It is also the same as cooperation, without putting any misunderstandings and hatred involved.
In the act of the mayor bringing together both his supporters and opponents together, he is displaying an act of co-operation or collaboration. He put the city's issues before his own opinions, which is a true quality of a leader.
Thus, the correct answer is collaboration.