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').

Water is present in all ____ phases in Earth s atmosphere.\Question: Choose the right answer from options given a) six b) nine c) two d) three
d

Astronomical observations suggest ____ or close to zero space-time curvature.\Question: Choose the right answer from options given a) six b) zero c) ten d) seven
b

Gravity is the force of attraction between any ____ objects.\Question: Choose the right answer from options given a) two b) nine c) four d) no

a