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').

[EX Q]: Stroke is the number ____ cause of death in the United States.\Question: Choose the right answer from options given a) ten b) nine c) one d) three
[EX A]: d

[EX Q]: Most toddlers find it hard to sit still for more than a few seconds, let alone ____ minutes.\Question: Choose the right answer from options given a) no b) three c) four d) zero
[EX A]: b

[EX Q]: Autism occurs in about four to five of every ____ thousand births.\Question: Choose the right answer from options given a) zero b) ten c) four d) seven
[EX A]:
b