What is the biggest employee-related COST to businesses, out of the following types?

I do not know but I assume Maternity leave because it lasts several months. But I am very surprised about the stress related issues that many managers have answered. I wasn't aware the extent of the problem. 

I dont think there are any downhills to these types. If they are not misused, and the job gets done in time and properly. You need to allow your employees those little pleasures in order for company to function. Except maybe smoking. Because of the health issues.

And I see a lot of people mention maternity leave. I think that should be completely left out of the list, because we are talking about raising the family and that should be put before your job. It is a basic physiology, something that cant be changed. In that regard, you wouldnt want to restrict lounch brakes, would you?

This is a very good question that would probably require a comparative study as I believe different demographic factors call for different results. However, in western countries, sickness mainly due to stress factors is increasing and becoming a very troublesome cause of inefficiency.

It will be maternity leave if more female married staff employed and then the sick leaves.

HI.. 

i think D & E is the biggest cost, a business is facing now a days.. because it takes your time and efficiency... and unnecessary browsing and chatting in office serve the purpose of losing cost.

i found majority of people having opened browser of Facebook, Tagged, linkedin, youtube bla bla blaaa..

which reduce their ability of attention, focus, concentration to their work.. and if employee is not focused then its your extra cost.. bearing by business and loss of work also..

According to me the biggest COST to an employee should be dis loyalty I know it is not the option given but if a person is not Loyal he will definitely do all if the above 

Theft of office materials 

Browsing the internet during work-hoursChatting in officeLeaving office during work hours

All of these are directly co related with being dis loyal to your work.

A. Stress-related issues? 

Because if he is stressed then he will do all the other in your list , except "G".

maternity leave followed by browsing the Internet during working hours

1. stress related issues

2. maternity leave...as u have to hire and train replacement. also your origginal employee looses his touch at work..hence re-training cost or it takes long time to get her back into fast pace. also she has lot of worries related to kid or family..hence more issues.

Low Effenciency ( Low Rate of real hours worked)

I am in the opinion that it is stress related issues since this could have a significant impact on the employess ability to perform. An uncalculated choice or move made during extreme stress could cloud judgement and prove far more expensive to the company than the other issues mentioned combined.