Ashish, the Marketing Head, Raman, the Assistant Manager and Jyoti, the Human Resource Manager of 'Senor Enterprises Ltd.' decided to leave the company. The Chief Executive Officer of the company called Jyoti the Human Resource Manager and requested her to fill up the vacancies before leaving the organisation. Informing that her subordinate Miss Alka Pandit was very competent and trustworthy, Jyoti suggested that if she could be moved up in the hierarchy, she would do the needful. The Chief Executive Officer agreed for the same. Miss Alka Pandit contacted 'Keith Recruiters' who advertised for the post of marketing head for 'Senor Enterprises Ltd., They were able to recruit a suitable candidate for the company. Raman's vacancy was filled up by screening the database of unsolicited applications lying in the office.
a. Name the internal/external sources of recruitment used by 'Senor Enterprises Ltd.' to fill up the above state vacancies.
b. Also state any one merit of each of the above identified source of recruitment.