The correct identification of a voltage source is a dry cell, which produces electric potential through chemical action. Other options like generators and thermocouples operate on different principles, such as mechanical motion and temperature differences. Thus, dry cells exemplify voltage sources based on chemical reactions. ;
The correct identification of a voltage source is the dry cell, which develops electric potential through chemical action. The other options misrepresent how voltage sources operate. Therefore, option B) Dry cell: chemical action is the right choice.
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