when a process is in a “blocked” state waiting for some i/o service. when the service is completed, it goes to the

It goes to the ready state.

Quick explanation

In a typical operating system process lifecycle, a process that was blocked (waiting for I/O) moves to the ready state once the I/O completes, where it waits in the ready queue for the CPU to be assigned again.

Processes never jump directly from blocked/waiting to running; they must pass through the ready state first.

Answer (fill‑in style):
When a process is in a “blocked” state waiting for some I/O service, when the service is completed, it goes to the ready state.

TL;DR: Ready state.

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