Final answer:
The correct option is: C) Rosin-core. Only rosin-core solder should be used for electrical work, as it contains a flux core that improves the quality of the solder joint. Acid-core solder, with its corrosive acid flux, is not recommended for electrical work.
Step-by-step explanation:
For electrical work, only rosin-core solder should be used. Rosin-core solder is solder that contains a flux core, which helps remove oxidation and improve the quality of the solder joint. Acid-core solder, on the other hand, contains a corrosive acid flux that is not recommended for electrical work.
The correct option is: C) Rosin-core. Only rosin-core solder should be used for electrical work, as it contains a flux core that improves the quality of the solder joint. Acid-core solder, with its corrosive acid flux, is not recommended for electrical work.