Databases store huge amounts of data on disk and must support fast search, insertion, deletion and range queries.

A B+ tree is a balanced multi-way search tree: all records are kept in the leaf nodes, which are linked together, and its height stays very small. So each lookup needs only a few disk accesses, and range queries are just a walk along the leaf chain.

Linked lists, queues and stacks need linear search, so they are not used for indexing.

Answer: (A) B+ tree