The ServiceNow platform is designed to create applications that use forms, workflow, and reporting to solve business problems. Forms are used to interact with data stored in tables, workflow is used to automate and orchestrate processes, and reporting is used to visualize and analyze data. The platform does not require low-level programming libraries or multimedia features, as it provides standard tools and technologies for application development.
References = ServiceNow Certified Application Developer Exam Specification, Application Development Platform - ServiceNow

In ServiceNow, tables can extend other tables, inheriting all fields and functionalities from the parent table. These inherited fields are integral to the structure and behavior of the child table.
A . No, inherited fields cannot be deleted from a child table: This is correct. Inherited fields are part of the child table's schema due to its extension of the parent table. Removing these fields would disrupt the inherent structure and relationships defined by the table hierarchy.
B . Yes, but only if they are text fields: This is incorrect. The data type of the field does not permit the deletion of inherited fields.
C . Yes, select the red X in the left-most column in the table definition: This is incorrect. Inherited fields do not have a delete (red X) option in the table definition, as they are not directly created on the child table.
D . Yes, but only if there has never been any saved field data: This is incorrect. The presence or absence of data does not affect the ability to delete inherited fields.
To modify the structure of inherited fields, consider the following approaches:
Field Visibility: Use client scripts or UI policies to hide the inherited fields on forms where they are not needed. This approach maintains data integrity while tailoring the user interface to specific requirements.
Form Layout Configuration: Adjust the form layout to remove inherited fields from specific views, ensuring they are not displayed to users in contexts where they are irrelevant.
These methods allow customization of the user experience without altering the underlying table schema or violating the inheritance principles established in the data model.

ServiceNow provides multiple ways to show messages to users in the UI, and the correct method depends on whether the message is meant for the top of the form or next to a specific field. In the GlideForm client API, ServiceNow documents g_form.addInfoMessage(String message) as the method that adds an informational message to the top of the form. This is the standard client-side approach for showing an info banner at the top area of the current form and is commonly used in Client Scripts and UI Policies to inform users about guidance, rules, or results of client-side logic. ServiceNow's GlideForm documentation specifically names this method and provides examples of its usage via g_form. By contrast, g_form.showFieldMsg() (and similarly named field-message functions) are used to display messages associated with a particular field location, not as a general blue banner at the top of the form. The option g_form.addInfoMsg() is not the documented default method name. Therefore, the correct answer is g_form.addInfoMessage().

https://developer.servicenow.com/dev.do#!/reference/api/paris/server_legacy/c_GlideSystemAPI#r_GS-nowNoT