In JIRA, JQL (JIRA Query Language) is used to filter and select a specific set of issues based on various criteria such as status, assignee, project, etc. Hence, using JQL, you can filter a specific set of issues for modification during Bulk Operations.

The correct option is Option 3: CSV Import/Export. CSV (Comma-Separated Values) Import/Export is a prevalent method for migrating data between various JIRA instances due to its simplicity and compatibility with different systems.

During a sprint, the team selects items from the product backlog to create a Sprint Backlog, which consists of the user stories and tasks that the team commits to completing within the duration of the sprint. This backlog guides the team's work during the sprint.

Custom workflows in JIRA can be optimized for large teams by simplifying and streamlining processes. This involves reducing unnecessary steps and transitions to minimize complexity and improve efficiency. By doing so, teams can maintain agility and adaptability while ensuring that workflows remain manageable and scalable as the team grows.

Velocity is the Agile metric used to measure the amount of work completed in a single iteration. It helps teams understand their capacity and productivity, aiding in better planning and forecasting for future iterations.

Managing projects effectively in JIRA involves utilizing project roles and permissions to control access and responsibilities. This ensures that large teams can collaborate efficiently without compromising data security. By defining clear project hierarchies and implementing best practices, teams can streamline workflows and enhance productivity.

In Scrum, the team holds a Sprint Review at the end of each sprint to review the work completed during the sprint and plan for the next sprint. This meeting allows for feedback and collaboration among team members and stakeholders.

To ensure that a custom field is displayed on an issue's view screen in JIRA, you need to add the field to the appropriate field configuration used by the project. Field configurations determine which fields are available on screens for particular issue operations. By including the custom field in the field configuration, you ensure that it appears on the issue view screen where users can easily access and interact with it.

While JIRA provides integration with version control systems like Git, "Commit" is not a native component of JIRA. A commit typically refers to a code change in version control systems but is not directly managed within JIRA.

In JIRA, you can manage user access by grouping them into logical units called "groups". These groups can then be assigned specific permissions to perform actions within the system. Thus, the correct term to fill in the blank is "groups".