According to Snapshot from Practice $8\mathrm{.}5,$ which of the following are obstacle$($s$)$ to implementing a central source to oversee project resource scheduling?

Multiple Choice

Managers did not trust colleagues in other departments.

Managers wanted to ensure that they would not have to give up power.

Managers wanted to protect their turf.

The company's culture was simply too inflexible.

All of these alternatives are the obstacles to implement a central source to oversee project resource scheduling.