One benefit of on-site day care services for employees is that a. employers are able to enforce longer work weeks b. employees can leave their children at work overnight c. employers can charge workers higher than normal fees d. employees can visit their children during the day

The correct answer is D. Employees can visit their children during the day

Explanation:

On-site daycare services for employees means there are specialized daycare facilities for the children of employees near to the place where they work or within it during day hours, this type of services have multiple advantages for employees that include not worrying about looking for other daycare services and spending more time with children. Indeed in most cases, employees are allowed to spend lunchtime and other breaks with children, also, once day work is over they can immediately see their kids. Thus, one benefit of on-site daycare services for employees is that "Employees can visit their children during the day".