A profit sharing plan may include all of the following EXCEPT:

A profit-sharing plan is primarily designed to distribute a portion of a company's profits to its employees as an incentive and a way to promote loyalty and productivity.

The correct answer identifies that a profit-sharing plan does not inherently have to include special death benefits for dependent children. While some retirement plans may provide death benefits or have provisions for beneficiaries, it is not a requirement of profit-sharing plans specifically.

In contrast, the other elements mentioned are more intrinsic to the characteristics and operational requirements of a profit-sharing plan. For instance, provision for employee pre-tax 401(k) contributions does exist within the framework of some profit-sharing plans, allowing employees to save for retirement in a tax-advantaged manner. Additionally, substantial and recurring company contributions are essential to ensure the plan effectively shares profits, affirming the plan's primary purpose of linking employee compensation to company performance. Lastly, a vesting schedule is commonly included in these plans to ensure that employees earn their benefits over time, reinforcing long-term employment and loyalty.

In summary, while death benefits for dependent children can be part of some benefit plans, they are not a standard feature or requirement of a profit-sharing plan, making this option the exception.