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

Ex Output:
a


Ex Input:
Lizards generally have ____ legs and movable eyelids.\Question: Choose the right answer from options given a) four b) two c) five d) zero

Ex Output:
a


Ex Input:
Cars also kill around ____ people each and every day in the UK through accidents.\Question: Choose the right answer from options given a) ten b) five c) no d) two

Ex Output:

a