Explanation/Reference: https://docs.servicenow.com/bundle/orlando-application-development/page/script/debugging/ concept/c_FieldWatcher.html

Extending an existing table such as the Task table when creating a new application has several benefits, such as:
You can repurpose existing fields by simply changing the label. For example, you can change the Short description field to Summary or Title for your new table.
You can use existing fields with no modifications. For example, you can use the Assigned to, Priority, and State fields for your new table without changing anything.
Existing logic from the parent table will be automatically applied to the new table. For example, you can inherit the Business Rules, Client Scripts, and UI Policies from the Task table for your new table.
The only option that is not true is d) All of the parent table records are copied to the new table. Extending a table does not copy any records from the parent table to the new table. It only creates a new table that inherits the fields and logic from the parent table.
References:
[Extend a table]
[Task table]

Reference:
A module is a navigation item that provides access to a feature or functionality in ServiceNow. Modules must have a link type, which determines how the module behaves when clicked. The following is a list of link types:
Assessment. This is a link type that opens an assessment, which is a survey or questionnaire that measures the effectiveness of a process or service.
List of Records. This is a link type that opens a list of records from a table or a saved filter.
Separator. This is a link type that creates a horizontal line to separate modules in the application menu.
Timeline Page. This is a link type that opens a timeline page, which is a graphical representation of the duration and sequence of events or tasks.
The following are not link types, but other module attributes or field types:
List of Records, Separator, Catalog Type, Roles. These are not link types, but a combination of a link type (List of Records), a module attribute (Separator), a field type (Catalog Type), and a user attribute (Roles).
List of Records, Content Page, Order, URL (from arguments:). These are not link types, but a combination of a link type (List of Records), a module attribute (Content Page), a field name (Order), and a link type argument (URL).
Assessment, List of Records, Content Page, Roles. These are not link types, but a combination of a link type (Assessment), a link type (List of Records), a module attribute (Content Page), and a user attribute (Roles). References: Modules, Create a Module

The statement that is true for this script fragment is that the method returns true if the currently logged in user has the x_my_app_user role or the admin role. The g_user.hasRole() method is a client-side method that checks whether the current user has a specified role or set of roles. If no role is specified, it returns true if the user has any role. If one or more roles are specified, it returns true if the user has any one of the specified roles. However, this method always returns true if the user has the admin role, regardless of the role parameter.
Therefore, in this case, the method returns true if the user has either the x_my_app_user role or the admin role.
Reference: User Object Cheat Sheet, Checking user permissions