The eventstats command in Splunk is used to compute and add summary statistics to all events in the search results, similar to the stats command, but without grouping the results into a single event(Option C). This command adds the computed summary statistics as new fields to each event, allowing those fields to be used in subsequent search operations or for display purposes. Unlike the transaction command, which groups events into transactions, eventstats retains individual events while enriching them with statistical information.