TASK DEFINITION: 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').
PROBLEM: Stable oxygen has eight protons and ____ neutrons.\Question: Choose the right answer from options given a) eight b) ten c) three d) zero

SOLUTION: a

PROBLEM: Most marine sediments are of ____ basic types.\Question: Choose the right answer from options given a) three b) ten c) two d) nine

SOLUTION: c

PROBLEM: Most abortions are safe and uncomplicated, and most women have ____ problems physically afterwards.\Question: Choose the right answer from options given a) no b) one c) zero d) five

SOLUTION:
a