Explanation: Storing spare "B" batteries in a dry place (A) is essential for their longevity and reliable performance. Moisture can cause corrosion on the battery terminals, leading to poor electrical contact and increased internal resistance. More importantly, moisture can create conductive paths across the battery's surface, resulting in a slow but continuous self-discharge, even when the battery is not in use. This parasitic current drains the battery's charge, significantly reducing its useful life and leaving it unprepared for use. Storing batteries in a hot place (B) is also detrimental. Elevated temperatures accelerate the internal chemical reactions within the battery, leading to a much faster self-discharge rate and increased degradation of the internal components. This can cause leakage, swelling, or even rupture, and drastically shortens the battery's overall lifespan. Storing them "anywhere" (C) is incorrect because it disregards these critical environmental factors for proper battery maintenance. Therefore, a dry environment is crucial for preserving battery integrity.