Which of the Following Defines Job Posting

Which of the following defines job posting?

A) It is a planned sequence of jobs through which employees may advance within an organization.
B) It is a procedure for advertising job openings within a company to existing employees.
C) It is a written description of the basic tasks, duties, and responsibilities required of an employee holding a particular job.
D) It is a purposeful, systematic process for collecting information on the important work-related aspects of a job.