Which of the following is considered a major reasons to conflict on projects Why?

All of them can cause a conflicts on projects, but the most one is a conflict in Resources, priorities, schedules

Thank you for invitation...

I'm with answer of En.Hatem labib..

Bad habits, defects, technology

all of them can be a reason for conflict 

Resources, priorities, schedules

Specially priorities, schedules and resources in order.

I think the main reasons are: Resources, priorities, schedules

Resources, priorities, schedules

 (I think it is (Resources, priorities, schedules

The reason is the Competition

I believe all of the mentioned above are major conflicts in a project... each can cause time delay, loss of budgetary money... poor structure ...

Resources, priorities and Schedule. A project can not work properly without planning and priorities. But more important Project needs to have the right Team.

In my experience the Team does it all, they are the people that everyday works on the activities and make the project move, the results of a Project is due to the Team in a very high percentage. Of course the Project Manager plays a big role in the equation, leading the team, controlling all tasks, dealing with the clients, contractors, the finances, HSE, etc, etc