Final answer:
A reusable resource in computing can be used by one process at a time without being depleted, and it includes things like semaphores and connection pools.
Step-by-step explanation:
The concept of a reusable resource in the context of computing refers to a type of resource that can be utilized by multiple processes or threads, either one at a time or concurrently, and is not diminished upon use. The correct answer to the question, what is the reusable resource, is:
a) that can be used by one process at a time and is not depleted by that use
This means that the resource does not get consumed permanently after a process is finished using it, and it can be used repeatedly. Such resources typically include things like semaphores, locks, connection pools, and threads, which are designed to manage concurrent access while ensuring data integrity and system stability.
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