The accuracy of collimation at a 60-inch SID must be:

The accuracy of collimation at a 60-inch source-to-image distance (SID) is a critical aspect of radiography and ensures that the area being imaged is properly covered while minimizing unnecessary radiation exposure to adjacent structures. The acceptable limit for collimation accuracy is typically defined in terms of how closely the actual beam edges align with the intended areas.

In this scenario, the correct answer reflects that the maximum allowable deviation from the intended collimated area is ±1.2 inches at a 60-inch SID. This standard is established by various imaging societies and regulatory agencies to ensure safety and quality in radiographic practices.

Maintaining this accuracy is essential not only for patient safety but also for diagnostic effectiveness; improper collimation can lead to suboptimal imaging results and unnecessary exposure. The other options either represent greater deviations than what is typically acceptable or do not align with established guidelines for collimation accuracy at a specified SID. Thus, ±1.2 inches serves as the most accurate reflection of the standard for collimation at a 60-inch SID.