Hardware model normalization is a feature that enables users to normalize the details, such as manufacturer, product, model, and device type, of their hardware and consumable models1.
Hardware model normalization uses the data from the Hardware Model Normalization Content Service, which is a cloud-based service that provides standardized information for thousands of hardware models1.
The key attribute in the model record that hardware model normalization uses to normalize inconsistent manufacturers and product names is the model number12.
The model number is a unique identifier for a specific product or model that is assigned by the manufacturer12. It is based on the United Nations Standard Products and Services Code (UNSPSC), which is a global classification system for products and services23.
Hardware model normalization compares the model number of the model record with the model number of the Hardware Model Normalization Content Service record and updates the model record with the normalized information, such as display name, manufacturer, product, and device type12.
The other options are not the key attribute that hardware model normalization uses to normalize inconsistent manufacturers and product names. The asset tag, the display name, the model category, and the asset tracking unit are either not unique or not based on the UNSPSC.
Reference:
1: Hardware Model Normalization - Product Documentation: Tokyo - ServiceNow
2: Hardware Asset Management overview - ServiceNow - Now Support
3: Product Documentation | ServiceNow
4: Automation Simplifies Hardware Asset Management - ServiceNow Blog

A blind audit is a type of inventory audit that does not provide any information about the expected assets in a location. The auditor scans all the assets in the location and compares them with the records in ServiceNow1.
To perform a blind audit, you need the Hardware Asset Management (HAM) application, which enables you to manage the lifecycle of your hardware assets, and the ServiceNow Agent mobile app, which allows you to scan asset tags and barcodes using your mobile device12.
The ServiceNow My Assets mobile app is used to view and request assets from the enterprise asset catalog, not to perform audits3.
The Software Asset Management (SAM) application is used to optimize software licenses and compliance, not to perform audits4.
The ITSM Asset Management application is used to track the financial, contractual, and inventory details of hardware and devices, not to perform audits. Reference:
1: Audit your inventory - Product Documentation: San Diego - ServiceNow
2: Enterprise Asset Inventory Management - ServiceNow
3: My Assets mobile app - Product Documentation: San Diego - ServiceNow
4: Software Asset Management - ServiceNow
5: IT Asset Management - ServiceNow

Explanation
Create transform map: A transform map is a set of field mappings that determine how the source data in the import set table is transformed into the target data in the hardware asset table. You can create a transform map by using the Load Data UI page, or by navigating to System Import Sets > Create Transform Map. You need to specify the source table, the target table, and the field mappings between them. You can also define coalesce fields, which are used to prevent duplicate records from being created or updated. For example, you can use the asset tag or the serial number as a coalesce field.
Load data: To load data into the import set table, you need to select a data source, such as a file, a JDBC data source, or a web service. You can use the Load Data UI page, or navigate to System Import Sets > Load Data. You need to specify the source type, the file name or the connection URL, the sheet number and the header row (if using a file), and the import set table name. You can also preview the data before loading it into the table.
Run transform map: To run the transform map, you need to navigate to System Import Sets > Transform Maps, and select the transform map that you created. You can then click on the Run Transform button, which will execute the field mappings and transform the data from the import set table to the hardware asset table. You can also view the transformation history, the transformation statistics, and the transformation log to monitor the progress and the results of the transformation.
References:
Importing Hardware Assets into ServiceNow, which provides a step-by-step guide on how to import hardware assets into ServiceNow using an excel spreadsheet, an import set table, and a transform map.
Hardware Asset Inventory Management, which explains how to streamline inventory stock orders, empower employees with a robust asset catalog, monitor stock depletions, track shipments, scan assets with a mobile device, and plan asset refresh cycles.
Getting Started with ServiceNow Hardware Asset Management, which provides general procedures and forms for performing asset lifecycle management activities in ServiceNow.

Explanation
A field service management (FSM) change task is a task that is created from a change request and assigned to a field service agent to perform work on a configuration item (CI) or an asset1.
An asset task is a task that is created from an asset record and linked to an FSM change task to track the work done on the asset2.
When an asset task is completed, the asset record associated to the task is automatically updated with the latest information, such as location, status, assignment group, assigned to, and so on2.
This feature removes the need to manually update the asset record after completing the FSM change task, saving time and ensuring accuracy2.
References: 1: Create a change task for field service 2: Asset tasks