Which type of storage is non-volatile and not under the direct control of the computer's central processing unit?

The correct choice is secondary storage, which refers to types of storage that retain data even when the computer is powered off. Unlike primary memory, which is volatile and directly managed by the computer's CPU for quick access, secondary storage includes devices like hard drives, solid-state drives, and external storage options such as USB drives.

These storage types are designed for long-term retention of data and are not directly accessed by the CPU in real-time. Instead, data is retrieved from secondary storage and loaded into primary memory before the CPU can manipulate it, making it an essential component for maintaining data persistence beyond active processing. The distinction between primary and secondary storage is fundamental in understanding how data management works in computer systems.

Other options provided lead to different concepts: primary memory is directly accessed and volatile, while dynamic and static data structures pertain to organization and management of data in programming rather than storage types. Therefore, secondary storage is the appropriate choice in describing non-volatile memory under indirect CPU control.