Answer:
C: Employees are assigned to one of four pay scales. Randomly select a pay scale and survey every employee in that pay scale
Explanation:
Looking at the given options, the one that will likely result in undercoverage will be option C. This is because even after assigning employees to any of the 4 payscales, when randomly selecting for survey, he picked only one pay scale and surveyed every on there. Since he didn't include at least one person in the other pay scales, he will not have covered every pay scale which he will need to make a conclusion on job satisfaction experienced by his employees.