Final answer:
The Spanish word that best completes the sentence is 'descargar'.
Step-by-step explanation:
The Spanish word that best completes the sentence is descargar.
In this sentence, the verb descargar means 'to download'. So the sentence would translate to 'Why do we use to close the discs download?'. However, it seems like the sentence is incomplete and there might be some confusion in the wording.
If you have any more questions or need further clarification, feel free to ask.
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