Answer:
The correct answer is "single replacement".
Step-by-step explanation:
The activity series is a representation of a series of metals that are organized according to their order of reactivity. They start from the highest order of reactivity to the lowest order of reactivity.
The purpose of the series is to determine which products are formed in single-displacement reactions. The higher-order metals replace the lower order metals if there are two of them in the same solution. If metal is higher in the series it is more reactive than a metal that is below it in the activity series.
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