Debugging client-side scripts in ServiceNow involves utilizing tools and methods that operate within the user
' s browser environment, as client-side scripts execute there.
* A. gs.addErrorMessage(): This function is used in server-side scripts to add error messages to the session and is not applicable for client-side debugging.
* B. g_form.addInfoMessage(): This client-side function displays informational messages to the user on the form. While primarily used for user communication, it can aid in debugging by confirming the execution of certain script sections.
* C. jslog(): This function logs messages to the JavaScript log, which can be viewed using browser developer tools. It ' s a valuable tool for debugging client-side scripts by providing runtime information.
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* D. gs.log(): This function logs messages on the server side and is not available in client-side scripting.
Additionally, developers can use the debugger; statement within their client-side scripts. When the browser ' s developer tools are open, encountering this statement will pause script execution, allowing for step-by-step inspection.

A Module Link type defines how the module opens in the content pane when the user clicks on it in the navigation pane1. The URL (from Arguments) link type allows you to specify a URL that opens the Application Properties page for the selected application2. The URL can include arguments that are evaluated at runtime, such as the application name or scope3.
References = 1: Module link types - ServiceNow Docs 2: Application properties - ServiceNow Docs 3: URL (from Arguments) - ServiceNow Docs

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.
Reference:
[Extend a table]
[Task table]

To allow a module to open a form for new record insertion, the Link type should be set to "Create new record" or similar.
From Platform App Design Docs:
"Modules control navigation behavior via the Link type setting. To insert records, use the 'Create record' or
'New record' link type."