Which action must be taken with dross on the solder surface?

The action that must be taken with dross on the solder surface is that it must not contact tinned or soldered items. Dross is a byproduct formed during the soldering process, consisting of oxides and impurities that rise to the surface of molten solder. If dross comes into contact with tinned or soldered components, it can lead to contamination, which negatively impacts the quality of the solder joint and can cause defects such as cold solder joints, reduced strength, and reliability issues.

By preventing dross from contacting soldered items, you ensure that the integrity of the solder joint is maintained, promoting better performance and longevity of the electrical assembly. This practice aligns with IPC standards, which emphasize the importance of maintaining a clean and uncontaminated soldering environment to achieve high-quality assemblies.

The other options suggest various ways of interacting with or managing dross, but they do not prioritize the critical aspect of preventing contamination of soldered items, which is paramount for achieving reliable and effective solder joints.