In a company, we need to find the central value of salaries of employees in all categories, i.e., I, II III, IV, then we must find
Median Salary
Median salary is best option as it represents the data in two equal parts.
Mean is not applicable as class I officer might draw salary Rs. 2 lakhs and class IV employee as Rs. 20,000. Then mean salary Rs. 1,10,000 is not correct. Similarly (c) is not correct.