Respuesta :
c. "Il faut que" is the correct answer. The phrase means "it is necessary", which when put into the rest of the sentence it translates as "It is necessary that you know the national emergency number."
Bonjour
A- Il est possible de= it's possible
B- Vous préfériez = you'd prefer
C- Il faut que = You have to
D- C'est dommage que = It's a pity that
Il faut que vous connaissiez le numéro d'urgence national
You have to know the national emergency number.
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