esta , lol I'm a native Spanish speaker and I'm doing this in class. so easy but I need to get my credits
According to the context, the correct word to complete the question is "este".
It is used to indicate something specific within a sentence and agrees in gender and number with the noun it modifies.
In the question "¿Quieres comprar esta trompeta o aquélla?", "esta" is the correct option since it indicates a closeness of what is mentioned with respect to the issuer and agrees in gender and number.
Therefore, we can conclude that according to the context, the correct word to complete the question is "este".
Learn more about demonstrative pronouns here: https://brainly.com/question/10695738
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