Explanation:

- Option 1: Identification and assessment of the different sources of recruitment

- This step involves identifying where potential candidates might be found, such as job portals, recruitment agencies, and internal references.

- Option 2: Selecting the most suitable source or sources

- After identifying different sources, the next step is choosing the most effective ones considering factors like cost, reach, and relevance to the required skills.

- Option 3: Inviting applications from the prospective candidates

- This involves reaching out to potential candidates and encouraging them to apply for the job, usually by advertising through selected sources.

- Option 4: All of the above

- This includes all the activities listed, making it a comprehensive selection.