Which of the following factors affects the resolution of penetrant indications?

The resolution of penetrant indications is significantly influenced by the sensitivity of the penetrant materials used. Sensitivity refers to the ability of the penetrant to identify and highlight small surface discontinuities. More sensitive penetrants can detect smaller flaws, which enhances the clarity and detail of the indications observed in the testing process. This means that the higher the sensitivity, the better the resolution of the defects identified, allowing for more precise analysis and evaluation of the test object's integrity.

The other factors, while they might have some influence on the test process, do not directly relate to the resolution of the indications like sensitivity does. For instance, the temperature of the penetrant can affect its viscosity and application properties, but it doesn't inherently improve or degrade the ability to discern defects once they are indicated. The color of the penetrant might aid visibility under certain lighting conditions, yet it does not affect the resolution as inherently as sensitivity does. Lastly, the age of the penetrant can lead to performance degradation, particularly in terms of application and effectiveness, but does not contribute to the resolution of the indications themselves in the same way that sensitivity does. Thus, opting for a penetrant with higher sensitivity plays a crucial role in ensuring that the resolutions of indications are maximally effective during testing