سوال ۱۹ کنکور ارشد علوم کامپیوتر ۱۴۰۱

PASSAGE 1 (data organization on tape)

Information is stored on the tape in magnetized units called bits which are similar to the bits in internal memory. Vertically, they form patterns such that every nine of them (eight bits of data plus a parity bit, used for error detection) are called a frame. A group of these frames forms a record of information, which may be either long or short. These records are separated from each other by marks called interrecord gaps, and a group of such logical records forms a physical record known as a block. Blocks, in turn, are organized as files, which are separated from each other by special characters.

19- A block ----------.