Given a sentence with a missing word, pick the answer option that best fills out the missing word in the sentence. Indicate each answer with its index ('a', 'b', 'c', 'd').

Smoking is responsible for one out of ____ American deaths.\Question: Choose the right answer from options given a) five b) six c) nine d) seven
a

Vaccinated newborns have protection for at least ____ years.\Question: Choose the right answer from options given a) four b) five c) two d) no
b

Jurassic rocks have ____ outcrops in the area but they are identified by bore holes.\Question: Choose the right answer from options given a) four b) three c) seven d) no

d