Which is a set of instructions covering those operations which lend themselves to a definite or standardized procedure without loss of effectiveness?

The correct answer is Standard Operating Procedure (SOP) because SOPs are specifically designed to provide clear, detailed, and structured instructions for performing operations consistently and effectively. They are used in various fields to ensure that processes are carried out in the same way each time, thereby minimizing risks associated with variability and error. This standardization is crucial for maintaining quality and efficiency in operations.

SOPs typically include step-by-step instructions that cover how to complete tasks in a precise way, ensuring that personnel can execute operations without ambiguity. This makes them particularly effective in environments that require adherence to strict protocols, such as healthcare, manufacturing, and laboratory settings, where deviations from standard procedures can lead to significant consequences.

Other options, while related to operational procedures and management, serve different purposes. Guidelines provide general recommendations rather than detailed instructions. Protocols may offer a structured plan of action but can be broader and less specific than SOPs. Policy manuals outline the organization's overall governance and operational policies but do not necessarily provide step-by-step procedures for everyday tasks.