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: Respiratory therapists complete two to ____ years of education.\Question: Choose the right answer from options given a) no b) one c) four d) eight

SOLUTION: c

PROBLEM: Hybridization is the practice of ____ different species interbreeding.\Question: Choose the right answer from options given a) no b) one c) two d) three

SOLUTION: c

PROBLEM: Natural cadmium is made of ____ isotopes.\Question: Choose the right answer from options given a) five b) eight c) four d) no

SOLUTION:
b