The passage argues that in the companies where employer pays a portion of ESI there is 22% less absentee in average than other companies that didn't offer ESI.
Lets analyze the statement which weakens the argument:
A. Results similar to those cited for the manufacturing sector have been found in other sectors of the economy where ESI is offered.
Strengthen the argument. Eliminate
B. At companies that offer ESI, employees have access to preventative health care such as regular check-ups, routine laboratory tests, and nutrition counseling.
Again is gives benefits of ESI and in a way strengthen the argument. Eliminate
C. Because initiating an ESI plan requires a lot of paperwork for the company, employees, and the insurance provider, doing so is complex and time-consuming.
This makes ESI a complex and time consuming and disadvantageous to employees. Keep this option.
D. Many firms in the manufacturing sector have improved workplace safety and decreased the occurrence of on-the-job injuries in the last five years, and most of these companies introduced ESI at the same time.
It says both workplace safety and decreased occurrence on job along with ESI have been implemented. So less absentee can be due to improved safety and decreased occurrence on job. Keep this as well.
E. In manufacturing firms where ESI is offered, the average productivity is 2% higher than it is in those firms where workers are not covered by an ESI plan.
Again strengthen the argument. Eliminate.
Of option C & D, D seems more correct as it provides other reason due to which less absentee may happen.
Correct answer is D.