Which sentence from the text BEST demonstrates the fact that the family had prepared for this type of emergency?

A.
"You all know the drill."

B.
By now, the wind was propelling the cold rain horizontally and relentlessly.

C.
"It's time to move out."

D.
The rain had let up even more, and I buried myself in my blanket, waiting for sunrise and my dad's approval—both of them slow in coming.

A. "You all know the drill."

The best sentence that demonstrates the fact that the family had prepared for this type of emergency is "You all know the drill."

To determine which sentence from the text best demonstrates the fact that the family had prepared for this type of emergency, we need to look for clues or indications of prior preparation. Let's analyze the given options:

A. "You all know the drill." - This sentence implies that the family is familiar with a specific procedure or plan, suggesting that they have prepared for such emergencies. It demonstrates their previous readiness.

B. "By now, the wind was propelling the cold rain horizontally and relentlessly." - This sentence describes the current weather conditions but does not necessarily indicate prior preparation.

C. "It's time to move out." - This sentence implies a sense of readiness and awareness of the situation, but it does not explicitly show that the family had prepared in advance.

D. "The rain had let up even more, and I buried myself in my blanket, waiting for sunrise and my dad's approval—both of them slow in coming." - This sentence does not provide any indication of the family's preparedness.

From these options, the sentence that best demonstrates the fact that the family had prepared for this type of emergency is:

A. "You all know the drill."

This sentence directly implies previous preparation and familiarity with a specific emergency plan or procedure.