Which command displays a summary of install and remove transactions?

The command that displays a summary of install and remove transactions is "yum history." This command provides a comprehensive list of transactions that have been performed by the package manager, including installations, removals, and updates. Each entry in the history allows you to see what packages were involved, when the transaction occurred, and its status, enabling you to track changes over time effectively.

Other options do not provide a summary of install and remove transactions in the same way. For instance, "rpm -q --last" lists recently installed packages but does not summarize actions like removals or overall transaction history. The "dnf transaction" command typically focuses on the status of ongoing transactions rather than summarizing past ones. Lastly, "yum info transactions" is not a valid command in Yum; the correct usage would be through the "history" command for transaction-related queries. Therefore, "yum history" is the appropriate choice for viewing a complete summary of transaction actions.