3. On the other hand, respondent department contended before the learned Single Judge that the petitioner was promoted on ad-hoc basis on the post of Executive Engineer during 1989, purely on temporary basis. The post of Executive Engineer is a selection post, where criterion for promotion is merit cum seniority. Petitioner was considered for the promotion to the regular post of Executive Engineer from the year, 1988 to 1993 year-wise but because of his low merit, he could not be promoted, as a result of which, private respondents, who were better in merit came to be promoted ahead of the petitioner. DPC considered the ACRs of relevant period of the petitioner as well as other persons, entitled to be promoted to the post of Executive Engineer. Respondents