Final answer:
The correct word to complete the question is '¿Cuándo?'
Step-by-step explanation:
The correct word to complete the question is ¿Cuándo?
- ¿Cuánto van al restaurante a cenar? (How much do they spend at the restaurant for dinner?)
- ¿Quién van al restaurante a cenar? (Who goes to the restaurant for dinner?)
- ¿Cómo van al restaurante a cenar? (How do they get to the restaurant for dinner?)
- ¿Cuándo van al restaurante a cenar? (When do they go to the restaurant for dinner?)
Therefore, the correct option is D. Cuándo.
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