The answer is "an infinitive verb".
Acabar de + infinitive is used to express an action that has ended prior the enunciation of the sentence.
For this case we can translate the sentence given as:
Emily: How is your car's gas efficiency?
Francisco: Very good, my car is going __________
The options are:
By definition, efficiency is about obtaining the greatest positive results with the minimum use of resources.
Then, if the efficiency of Francisco's car is very good, then the car is twenty miles traveled per liter of gasoline used.
Emily: How is your car's gas efficiency?
Francisco: Very good, my car is going Twenty km per liter
ANswer:
20 km por litro
Option C
1.) Los niños so bajos.
2.) Los niños so altos.
3.) Los niños son altos.
4.)Los niños son inteligentes.
All of the sentences have something incorrect some forget the tilde and some have misspelled words. This is how all the sentence should look if they were correct.