GMAT Critical Reasoning (CR) | Re: A requirement of traditional pension plans is that an employee work fo

A requirement of traditional pension plans is that an employee work for a company a number of years before gaining full rights to benefits from the company’s plan on retirement. Companies used this requirement to help them retain employees, but recent regulations have substantially reduced the number of years of work a company can require.
Nevertheless, companies have not experienced any significant loss of employees.

Which of the following, if true, helps to explain why companies are not experiencing