Final answer:
Removable devices such as USB flash drives are easily lost and can be used for espionage. Microprocessors revolutionized computing by allowing for efficient processing of large amounts of information, leading to advances in modern computer technology.
Step-by-step explanation:
The type of device that can be easily lost or stolen or can be used for espionage is c) removable devices. Removable devices such as USB flash drives, external hard drives, and memory cards are portable, making them convenient for transferring data but also susceptible to being misplaced or targeted for theft. Furthermore, due to their portability and the ability to store large amounts of data, removable devices can be used to smuggle sensitive information out of a secure environment, making them a tool for espionage.
The device that made it possible for digital computers to efficiently process large amounts of information is the microprocessor. Before the advent of microprocessors, computers relied on larger, room-sized processors that were far less efficient. The microprocessor represents a significant leap in computing technology, enabling the miniaturization and increased processing power that are at the core of modern computers.