Which of the following is an employee cannot be required to do without additional compensation?

The correct answer, which states that an employee cannot be required to work more than 8 hours a day without additional compensation, is rooted in labor laws designed to protect workers. In many jurisdictions, the standard work period is defined as 8 hours a day, and working beyond that typically qualifies as overtime. Overtime pay is mandated to ensure that employees are compensated fairly for extra hours worked, thus incentivizing employers to limit excessive work hours without additional payment.

While working during holidays and weekends can be required depending on the employer's policies, various laws may also stipulate that these hours warrant premium pay or time-off balances. Working without breaks, although often frowned upon, does not necessarily trigger additional compensation unless it violates labor standards that mandate rest periods. Hence, option A clearly aligns with the premise of requiring additional compensation for hours worked beyond the standard daily limit.