The correct answer is: C. Random file
A random file is a file that can be accessed directly, without having to read through all the preceding data. This is done by using an index, which is a table that maps file locations to data values.
A sequential file is a file that can only be accessed in order, from beginning to end. This is because the data in a sequential file is stored in a linear fashion, with no index.
A serial file is a type of sequential file that is stored on a magnetic tape. Magnetic tapes are a type of storage medium that is used to store large amounts of data. Serial files are typically used for backup purposes, as they can be easily read and written to.
An indexed file is a type of random file that uses an index to store the location of data values. This allows for faster access to data, as the index can be used to directly locate the desired data value.
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