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').

Q: Many aneurysms have ____ symptoms until they burst.\Question: Choose the right answer from options given a) no b) five c) six d) seven

A: a
****
Q: All mass spectrometers consist of ____ distinct regions.\Question: Choose the right answer from options given a) three b) one c) two d) zero

A: a
****
Q: Electromagnetic changes are at the speed of light and reach Earth within ____ minutes.\Question: Choose the right answer from options given a) five b) two c) zero d) eight

A:
d
****