Which of the following describes a corrective measure rather than an adverse action?

A letter of instruction serves as a corrective measure because it is typically intended to address and rectify a specific behavior or performance issue without imposing severe penalties. This type of communication provides feedback and guidance to an employee, outlining areas for improvement, while maintaining the employee's current position and standing within the organization.

In contrast, dismissal, salary reduction, and demotion are all forms of adverse action that represent significant penalties or punishments for an employee's performance or behavior. These actions can negatively impact an employee's career and financial status and are often seen as steps taken after corrective measures have failed or in cases of serious misconduct. Hence, the letter of instruction stands out as a tool for correction and development, aiming to foster improvement rather than impose punitive consequences.