The correct answer is C. A hashed file.
A hashed file is a data structure that uses a hash function to map keys to file locations. The hash function is a mathematical formula that converts a key into a numeric value. The numeric value is then used to calculate the file location of the record.
A tree file is a data structure that uses a tree data structure to store data. The tree data structure is a hierarchical data structure that stores data in a way that allows for efficient lookups.
An indexed file is a data structure that uses an index to store data. The index is a data structure that stores the location of records in a file. The index allows for efficient lookups of records in a file.
A sequential file is a data structure that stores data in a linear fashion. The records in a sequential file are stored one after the other. Sequential files are not as efficient as other data structures for lookups, but they are simple to implement.
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