Which of the following is not a linear data structure?

A binary tree is a hierarchical, non-linear data structure where each node branches to at most two children.

An array stores elements in one continuous sequence, making it linear.

A queue arranges elements in a single line served first-in first-out, so it is linear.

A CPU is a hardware processor and not a data structure at all.

Linear structures place data one after another, while a tree spreads it across levels.

Trees suit hierarchical data like file systems and search indexes.