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').

Traditional neon electrifies the inert gas from ____ directions.\Question: Choose the right answer from options given a) two b) nine c) one d) six
a

Hydra has ____ distinct methods of reproduction, asexual and sexual.\Question: Choose the right answer from options given a) two b) zero c) no d) ten
a

Atrial fibrillation increases a person s stroke risk by ____ times.\Question: Choose the right answer from options given a) six b) two c) eight d) ten

a