Final answer:
The best Spanish word to complete the sentence is "esta" which means "this" and agrees in gender with the noun "comida".
Step-by-step explanation:
The best Spanish word to complete the sentence "¿Quieres compartir (that) comida?" is esta. The word "esta" means "this" and it matches with the feminine noun "comida" which means "food."
Using "ese" instead of "esta" would be incorrect because "ese" means "that" (referring to something masculine) and it does not agree in gender with "comida."
Therefore, the correct completion of the sentence would be "¿Quieres compartir esta comida?" which translates to "Do you want to share this food?"
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