Which of the Following Is a Limitation of Recruiting from Within

Which of the following is a limitation of recruiting from within the organization?
Most entry-level jobs are filled with current employees.
In firms with a promote-from-within policy, positions are rarely filled externally.
If there is a job posting policy, external candidates can only be considered if there are no qualified internal candidates.
If positions are vacated unexpectedly, there may be no qualified internal candidates.
All of the above are limitations of recruiting from within.