What do you understand by "objectivity"? Highlight its relevance for a public servant.

Objectivity means the state or quality of being true and keeping aside one’s emotions, biases, prejudices. Objectivity is mind independent and object specific. In public life, it means giving equal treatment to people in equal situation irrespective of any other factor i.e being fair.
Civil servants enjoy immense power and are required to make decisions and defend them. Objectivity in decision making eliminates the possibilities of undue favour to any one at the cost of other persons. It inhibits impartial judgement. Objectivity allows civil servants to take decision on the merits of the case and take due account of expert advice. For example District collector in making appointments needs to give priority to merit rather than other factors like the caste or background of the candidate.
Objectivity may not be ethical solution in all cases like same fine cannot be imposed on both rich and poor, which may be objective but not fair. Objectivity at times is regarded  as clerical expectation as most of the decision making at higher level is subjective while objective calculation is done by clerks.
In public life objectivity as a value must strives for in all interaction but at many times being objective become difficult. Fairness as a value closest to objectivity can be practiced which progressively leads to objectivity.