Final answer:
The physical infrastructure service includes laptops and rack servers, as they are tangible components used in IT operations, unlike desktop operating systems which are software.
Step-by-step explanation:
The correct answer is options b. Laptop and c. Rack server. Physical infrastructure service in the context of technology typically refers to the hardware and facilities that support the functioning and management of an IT environment.
This includes the equipment such as servers, computers, networking hardware, and data center facilities necessary to operate and administer enterprise IT environments and services.
Desktop operating systems, on the other hand, are software platforms that enable users to interact with the computer and run applications.
They do not constitute physical infrastructure. In contrast, laptops and rack servers are tangible, physical components that are essential parts of the infrastructure needed for IT operations.
A laptop is a portable computer that can be part of various network environments, while a rack server is a space-saving server housed in a frame or rack, commonly used in data centers and enterprise IT setups.