In computing, which system allows devices to send interrupts to the OS?

The Vectored Interrupt System is the correct choice because it provides a structured way for devices to send interrupts to the operating system. In this system, each device has a unique identifier (or vector) that allows the CPU to quickly determine which device is signaling an interrupt. When an interrupt occurs, the system quickly looks up the vector associated with that device, allowing it to execute the appropriate interrupt service routine (ISR). This efficient mechanism minimizes latency and helps maintain system responsiveness, as the OS can directly respond to specific interrupts without needing to check each device in sequence.

Other systems, while important, do not facilitate interrupts in the same way. Polling requires the CPU to actively check the status of each device, which can lead to inefficiency and delay in responding to events. Direct Memory Access (DMA) allows devices to transfer data directly to memory without CPU intervention but does not handle interrupts directly. Interrupt Masking is a technique used to enable or disable interrupts but doesn't send them to the OS; it controls which interrupts are allowed to be processed when an interrupt occurs.