Explanation
The main components of an APEX workspace homepage are:
Gallery: This component displays various sample applications, blueprints, plug-ins, themes, and learning resources that you can use to get started with Oracle APEX.
SQL Workshop: This component allows you to view and manage the database objects in your schema, such as tables, views, indexes, etc. You can also use this component to run SQL queries or scripts, load or unload data from the database, generate DDL statements, view object reports, and restore dropped objects.
App Builder: This component allows you to create and edit your applications using the Create Application Wizard or the Page Designer. You can also use this component to import or export applications from files or URLs, run or debug applications, manage application settings, and access various utilities.
The other option is incorrect because:
RESTful Services: This component is not part of the APEX workspace homepage. It is part of the SQL Workshop component. It allows you to create and manage RESTful web services based on your database objects or SQL queries.
Verified References: [About the Workspace Home Page] [About SQL Workshop] [About App Builder]

Explanation
A theme is a collection of templates and stylesheets that define the layout and appearance of an application.
You can create a custom theme for an application by using the Create Theme Wizard or by copying an existing theme. If you want to use a custom theme for anotherapplication in the same workspace, you can copy the theme to that application by using the Copy Theme option in Shared Components. However, if the master theme (the original theme) may still require changes, you need to subscribe the copied theme to the master theme and refresh the theme whenever there are changes in the master theme. This solution guarantees that any changes to the master theme are reflected in the copied theme by using a synchronization process that updates templates and stylesheets based on their subscription status. Verified References: [Creating Themes - Oracle Help Center], [Managing Theme Subscriptions - Oracle Help Center]

Explanation
You can apply an authorization scheme for the following components in APEX:
A specific control such as a region, item, or button. You can select an authorization scheme from the Authorization Scheme list on the attributes page of the control. This will control the rendering and processing of the control based on the user privileges12.
A page. You can select an authorization scheme from the Authorization Scheme list on the Security page of the page definition. This will control the access to the page based on the user privileges12.
An entire application. You can select an authorization scheme from the Authorization Scheme list on the Security Attributes page of the application definition. This will control the access to the entire application based on the user privileges12.
You cannot apply an authorization scheme for a session, as a session is not a component in APEX. A session is a stateful connection between a browser and the APEX engine that persists across multiple requests and responses3. You can control session security by using session state protection, session expiration, and session isolation4.

Explanation
You can create a report in any of these three methods:
Create a report as a new page in an application by using the Create Page Wizard. This wizard guides you through the steps of selecting a page type, defining attributes, selecting a source (such as SQL query or table), and adding items or buttons.
Create a report when you create a new database application by using the Create Application Wizard.
This wizard allows you to generate one or more reports based on existing tables or views in your schema. You can also create a report and form on the same table or view.
Create a report region on a page in an application by using the Page Designer. This tool allows you to drag and drop a region type (such as Classic Report, Interactive Report, or Interactive Grid) onto the page and define its attributes and source.
The other option is incorrect because:
You cannot create a report from Object Browser. Object Browser is a tool that allows you to view and manage the database objects in your schema, such as tables, views, indexes, etc. You can only run SQL queries or scripts from this tool, not create reports.
Verified References: [Creating Database Applications] [Creating Pages] [Creating Regions] [Using Object Browser]

Explanation
There are three different ways in which you can add a checkbox to a page in APEX:
Drag and drop the checkbox item into the Layout pane: In Page Designer, you can drag and drop items from the Gallery pane into the Layout pane to create them on your page. To create a checkbox item, expand the Items node in the Gallery pane and drag and drop Checkbox into the Layout pane.
Right click Body in the Rendering Tree and add a New Page Item as Checkbox Type: In Page Designer, you can right click any node in the Rendering tree andselect Create to create a new component under that node. To create a checkbox item under the Body node, right click Body and select Create > New Page Item > Checkbox.
Use the context sensitive menu in the Gallery pane: In Page Designer, you can use the context sensitive menu in the Gallery pane to create items on your page. To create a checkbox item using this method, expand the Items node in the Gallery pane and right click Checkbox. Then select Create Checkbox.