It's ....A ...because as should have been used, meaning which. I will refuse his demands which are outrageous.
But unless has nothing to do with the context provided in.... C ....because until should have fitted here.
Answer:
Airplane crash.
Explanation:
Billy knows the airplane will crash, but he says nothing. The passengers are entertained by a barbershop quartet. The group sings lewd, racist songs to entertain Billy's father-in-law. When the plane crashes into Sugarbush Mountain, Vermont, everyone is killed except Billy and the copilot.
Answer:
The answer for this one is D
It would cause the reader to think that too. and it could confuse the reader if the assumption is contradicted later on in the story.
hope i helped!